Chapter 12

The Rejection of Apollinarianism

Why the Church Insisted Christ Has a Human Soul

Introduction: A Heresy That Matters Today

In the fourth century, the Christian church fought one of its most important battles — and it was a battle most Christians today have never heard of. It was not a fight about whether Jesus is God. The church had already settled that question at the Council of Nicaea in 325. This new battle was about something that might seem surprising at first. It was about whether Jesus has a human soul.

The man at the center of this controversy was Apollinarius of Laodicea (sometimes spelled Apollinaris), a respected bishop and a devoted defender of the Nicene faith. Apollinarius was no villain. He loved Christ. He fought against Arianism. He believed firmly that Jesus is truly God. But in his eagerness to protect the unity of Christ's person, Apollinarius made a move that the church ultimately judged to be devastating. He denied that Christ has a complete human nature — specifically, he denied that Christ possesses a human rational soul. In Apollinarius's view, the divine Word (the Logos) took the place of Jesus's human mind and soul. Christ had a human body, yes — but His inner life, His thoughts, His will, His rational capacities were all simply the divine Logos functioning through that body.

The church's response was swift, forceful, and nearly unanimous. Apollinarianism was condemned at the Synod of Alexandria (362), the Council of Rome (377), the First Council of Constantinople (381), the Council of Chalcedon (451), and the Second Council of Constantinople (553). The condemnation was repeated again and again — five major councils over nearly two centuries. No other Christological error has been so thoroughly and persistently rejected by the early church. The reason is simple: the church understood that if Christ does not have a human soul, He does not have a complete human nature. And if He does not have a complete human nature, He cannot save us.

Why does this ancient controversy matter for us today? Because I believe that modern Christian physicalism — the view that human beings are purely physical organisms with no immaterial soul — creates the very same problem that Apollinarianism created. The routes are different, but the destination is the same. Apollinarianism denied that Christ has a human rational soul by replacing it with the divine Logos. Physicalism denies that any human being has an immaterial soul — it says the soul simply does not exist. The result for Christ is identical: He lacks an immaterial human soul. And that, as we will see, is precisely what the early church condemned.

In this chapter, I want to walk us through the Apollinarian controversy carefully and thoroughly. We will examine what Apollinarius actually taught and why he taught it. We will listen to the church's response — especially the magnificent argument of Gregory of Nazianzus, whose famous axiom "what is not assumed is not healed" became the definitive refutation of Apollinarianism. We will look at the conciliar condemnations and understand why the church regarded this issue as non-negotiable. And then we will draw the critical parallel to modern physicalism and explain why, in my judgment, physicalism about Christ's human nature is structurally equivalent to the heresy the church already condemned.

Who Was Apollinarius, and What Did He Actually Teach?

Before we look at the church's rejection of Apollinarianism, we need to understand what Apollinarius was actually trying to do. This is important, because Apollinarius was not a reckless heretic. He was a careful thinker who was trying to solve a genuine theological problem. Understanding his concern will help us appreciate both the power of his proposal and the reasons it ultimately had to be rejected.

Apollinarius of Laodicea (c. 310–390) was a bishop, a prolific writer, and a passionate defender of Nicene orthodoxy. He stood firmly against the Arians, who denied that the Son is fully divine. In fact, Apollinarius was a friend and ally of Athanasius, the great champion of Nicene theology. His Christological thinking was driven by a legitimate worry: how can we affirm that Christ is truly one person — a single, unified subject — if He has both a complete divine nature and a complete human nature? If Christ has a divine mind and a human mind, a divine will and a human will, doesn't that give us two persons rather than one? Doesn't it risk the very problem that would later be called Nestorianism — splitting Christ into two separate subjects?¹

Apollinarius's concern was real, and we should not dismiss it too quickly. The unity of Christ's person is a central commitment of orthodox Christology. The Son of God is not two people living in one body. He is one person — one "I," one subject of experience — who is both divine and human. Apollinarius took this seriously and tried to find a way to guarantee it.

His solution drew on the anthropological framework of his day. Apollinarius held a tripartite (three-part) view of human nature. He believed that a human being is composed of three elements: a body (sōma, σῶμα), a lower soul or animating principle (psychē, ψυχή) that gives the body biological life and sensation, and a rational soul or mind (nous, νοῦς) that is the seat of thought, will, and self-directed action.² In Apollinarius's scheme, it is the nous — the rational mind — that is the decisive element that makes a human being a person. The nous is the center of consciousness, the directing intelligence, the personal agent.

With this framework in place, Apollinarius reasoned as follows. If the divine Logos already possesses a rational mind — and of course He does, since the Logos is the eternal Mind of God — then there is no need for Christ to have a second rational mind, a created human one. In fact, adding a created human nous would create the very problem Apollinarius feared: two personal agents, two centers of thought and decision, which would amount to two persons. So Apollinarius proposed that in the Incarnation, the divine Logos replaced the human nous. Christ has a human body. He may even have a lower soul (psychē) that governs biological and sensory functions. But His rational mind, His personal center, His directing intelligence — that is the divine Logos itself. As Apollinarius put it, the Logos joined with a human, fleshly nature to form a substantial unity, and through this union constituted a human being — a being of body and spirit. But the "spirit" in Christ is the divine Logos, not a created human mind.³

Apollinarius also applied the maxim popular in his day that "two complete entities cannot become one."⁴ If both the divine nature and the human nature are complete — each with its own mind, its own will, its own personal agency — then their union would not be a true Incarnation (one person becoming human) but a combination of two persons. It would be, as Apollinarius saw it, like putting two complete people into one body. That is not the Incarnation. The Incarnation is the one divine Person of the Son taking on flesh. So the Son takes on a body, but He does not take on a second mind to compete with His own.

There is a certain elegant simplicity to this scheme, and we should acknowledge it. As Michael Wilkinson observes, the symmetry between the soul-body composition of a normal human being and the Word-flesh composition of Apollinarius's Christ gave the view a surface-level coherence that was logically satisfying at first glance.⁵ In a normal human being, the soul directs the body. In Christ, the Logos directs the body. The structure is parallel. Everything fits neatly.

But as the church came to see, this neatness came at an enormous cost.

The Fatal Problem: An Incomplete Human Nature

The fundamental problem with Apollinarianism is straightforward, and it is devastating. If Christ does not have a human rational soul — a human mind, a human will, a human center of thought and decision — then Christ is not fully human. He has a human body, yes. But a body without a rational soul is not a human being. It is, as Gregory of Nyssa bluntly put it, an animal. A human body animated by divine power alone, without a genuine human mind, is something other than a man. It is a hybrid — partly divine, partly animal, but not truly and completely human.⁶

Wilkinson's analysis of Apollinarianism in Crowned with Glory and Honor brings this into sharp focus. The self-determining mind (nous autokīnētos, νοῦς αὐτοκίνητος) is, in Apollinarius's own framework, the decisive ontological element that transforms a mere body into a human being. Each self-determining mind has its own body and substantial being. Yet Apollinarius denied Christ exactly this — the one thing that makes a person human in his own system. Without a human nous, the Apollinarian Christ has the capacity for bodily movement but not genuine human action. All that a human soul adds to human existence — knowledge, will, love, moral deliberation, the capacity to suffer inwardly, the ability to choose, the power to overcome temptation — is missing from the one who is supposed to be the model for all humanity.⁷

Wilkinson captures the irony perfectly. By starting with the composition of a normal human being and extending that framework to Christ, Apollinarianism actually makes Christ less than a normal human being. The very paradigm that was supposed to explain the Incarnation ended up "mutilating the humanity of Christ."⁸

This is why the Council of Chalcedon (451), in its famous Definition, insisted that Christ is "truly man, of a rational soul and body" (ek psychēs logikēs kai sōmatos, ἐκ ψυχῆς λογικῆς καὶ σώματος), and "consubstantial with us according to the Manhood." The phrase "rational soul and body" was chosen precisely to exclude Apollinarianism. A "rational soul" (psychē logikē) is a soul that has the capacity for reason, thought, and will — the very thing Apollinarius denied Christ possessed. The council was not using these words carelessly. They were drawing a line in the sand. Christ's human nature is not merely a body. It is a body united to a rational soul. Both are essential. Remove either one, and you no longer have a complete human nature.⁹

Gregory of Nazianzus and the Axiom That Changed Everything

No one saw the problem with Apollinarianism more clearly, or stated the response more powerfully, than Gregory of Nazianzus (c. 329–390). Gregory was one of the three great Cappadocian Fathers — along with his friend Basil of Caesarea and Basil's brother Gregory of Nyssa — who shaped the church's orthodox theology in the crucial decades after the Council of Nicaea. Gregory of Nazianzus was a brilliant theologian, a gifted poet, and a fearless defender of the faith. He served briefly as the bishop of Constantinople, and his theological orations are among the most celebrated writings in the history of Christian thought.

Gregory's response to Apollinarianism is found primarily in his Epistle 101, also known as To Cledonius the Priest Against Apollinarius. This letter contains what is arguably the most famous sentence in the entire Apollinarian controversy — indeed, one of the most famous sentences in the history of Christian theology:

"For that which He has not assumed He has not healed; but that which is united to His Godhead is also saved."¹⁰

In the original Greek, the key phrase is: to gar aproslepton, atherapeuton (τὸ γὰρ ἀπρόσληπτον, ἀθεράπευτον) — "the unassumed is the unhealed." Let me break this down, because the logic is profound and its implications are far-reaching.

Gregory's argument rests on a soteriological principle — that is, a principle about salvation. Here is the logic, step by step:

Step 1: Human beings need redemption in every aspect of their nature — body, soul, and mind. We are not fallen only in our bodies. Our minds are darkened. Our wills are corrupted. Our inner lives are disordered. The deepest dimensions of human brokenness are not physical but spiritual and rational — our rebellion against God, our distorted desires, our enslaved wills, our darkened understanding.

Step 2: Redemption requires assumption. The Son of God must take on — must assume — what He intends to save. This is the Incarnation's inner logic. The Son did not save humanity from a distance, by issuing a decree from heaven. He entered into our condition. He took on our nature. He became what we are in order to heal what we are. As the author of Hebrews puts it, "He had to be made like his brothers in every respect" (Heb. 2:17, ESV).

Step 3: If Christ did not assume a human rational soul, then the human rational soul is not redeemed. The unassumed is the unhealed. If the Son took on a body but not a soul, then He has addressed the body but left the soul untouched. But the soul is where the deepest problem lies. The soul is the seat of sin, decision, and relationship with God. It is the rational soul that rebels, that chooses evil, that turns away from God. If Christ did not assume a human soul, then He did not enter into the deepest dimension of human brokenness.

Step 4: Therefore, Apollinarianism defeats the very purpose of the Incarnation. If the Son came to save us — and if the human soul is the very part of us most in need of saving — then the Son must have assumed a human soul. To deny Christ a human soul is to deny that He can redeem the most important part of who we are.

Gregory made the point with characteristic directness and power:

"If only half Adam fell, then that which Christ assumes and saves may be half also; but if the whole of his nature fell, it must be united to the whole nature of Him that was begotten, and so be saved as a whole."¹¹

This is a stunning argument, and I find it completely persuasive. Think of it this way. Imagine someone who has both a broken arm and a deadly cancer growing inside their body. A doctor who sets the broken arm but ignores the cancer has not healed the patient. The patient will die — not from the broken arm, but from the disease that was never addressed. Similarly, if Christ heals our bodies (by assuming a body) but never enters into our souls (because He has no human soul), then He has treated the less serious condition while ignoring the fatal one. Our bodies are not the primary locus of our problem. Our souls are. It is in the soul — the mind, the will, the inner person — that sin dwells, that rebellion takes root, that alienation from God begins. If Christ did not assume a human soul, then the very center of our brokenness remains untouched by the Incarnation.

Gregory's axiom became the definitive framework for evaluating any Christological proposal. Does this model give Christ a complete human nature? Does it affirm that the Son assumed everything that needs to be redeemed? If not, the model fails — not because it is philosophically inelegant, but because it undermines the salvation that the Incarnation was designed to accomplish.

Gregory of Nyssa: The Extended Critique

Gregory of Nazianzus was not alone in his opposition. His contemporary Gregory of Nyssa (c. 335–395), the younger brother of Basil of Caesarea, mounted an extensive philosophical and theological critique of Apollinarianism in his work Antirrheticus adversus Apollinarem (Against Apollinarius). Gregory of Nyssa's critique is longer and more detailed than his namesake's, and it approaches the problem from a different angle.

Where Gregory of Nazianzus focused primarily on the soteriological problem — what Apollinarianism means for our salvation — Gregory of Nyssa focused on the anthropological problem — what Apollinarianism means for Christ's humanity. His central argument can be stated simply: a human body without a human mind is not a human being. It is an animal.

We are human beings not merely because we have bodies. Animals also have bodies. What makes us human is our rational nature — our capacity to think, to reason, to make moral choices, to love, to worship, to relate to God as personal beings. If Christ had a human body but no human rational soul, then He did not become a human being. He became something less — a kind of divine-animal hybrid that has no parallel in reality. Gregory of Nyssa argued that Apollinarianism makes Christ a composite creature — part God, part animated flesh — but not truly man. The Incarnation, on Apollinarianism, is not really God becoming human; it is God taking on an animal body.¹²

Gregory of Nyssa's broader work on the human soul is also relevant here. He understood the soul as "an essence which has a beginning; it is a living and intellectual essence which by itself gives to the organic and sensory body the power of life and reception of sense-impressions as long as the nature which can receive these remains in existence."¹³ In Gregory's framework, only human beings possess "the true and perfect soul," while plants and animals have merely "vital energy" rather than the soul proper. This narrowing of the definition made the soul something distinctly human. If Christ lacks this distinctly human soul, He is not distinctly human.

Gregory of Nyssa also pressed the Incarnation's logic in the other direction. The whole point of the Incarnation is that the Son becomes what we are. We are rational souls embodied — thinking, willing, loving persons who inhabit physical bodies. If the Son did not take on a rational soul, then He did not truly become what we are. He did not enter into our full condition. He took on our flesh but not our inner life. And it is our inner life — our thoughts, our choices, our moral struggles, our relationship with God — that most needs to be redeemed.

Basil of Caesarea and the Breadth of the Opposition

The opposition to Apollinarianism was not limited to the two Gregories. Basil of Caesarea (330–379), the eldest of the Cappadocian Fathers, also raised concerns about Apollinarius's Christology, though he did so more cautiously because of his former friendship with Apollinarius. Basil recognized that denying Christ a human mind would compromise both His genuine humanity and His role as our representative before God. If Christ does not share our rational nature, then He does not truly stand in our place. He cannot be our mediator if He does not share the very capacity — rational, moral agency — that defines our relationship with God.¹⁴

The Antiochene theologians — those associated with the theological school of Antioch — also opposed Apollinarianism, though they did so from a somewhat different angle. The Antiochene tradition emphasized the completeness and integrity of Christ's human nature, including His human will and human rational activity. They insisted that the Gospel portrait of Jesus — a man who grows in wisdom, who is tempted, who struggles in prayer, who makes human decisions — requires a genuine human mind. A divine Logos operating a body like a puppeteer pulling strings does not match the Jesus we meet in the Gospels. The Antiochenes rightly recognized that the biblical portrait of Christ presupposes a real inner human life — real human thoughts, real human emotions, real human deliberation.¹⁵

The breadth of the opposition is itself significant. Apollinarianism was not rejected by one school of thought or one geographical region. It was opposed by Alexandrians (who normally emphasized the divine unity of Christ) and Antiochenes (who normally emphasized the human integrity of Christ). It was opposed by the East and the West. It was opposed by councils in Rome and councils in Constantinople. The consensus was virtually universal. This tells us something important: the church understood that the issue of Christ's human soul was not a peripheral matter of philosophical speculation. It was a matter of fundamental orthodoxy — a question on which the entire structure of Christian salvation depends.

The Conciliar Condemnations: A Non-Negotiable Verdict

Let us trace the conciliar condemnations of Apollinarianism, because their number and frequency tell us how seriously the church regarded this issue.

The Synod of Alexandria (362): This synod, presided over by Athanasius himself, addressed the question of Christ's humanity in the context of the post-Nicene debates. While it did not name Apollinarius directly (his distinctive views were still developing), the synod affirmed that the Savior's body was not without a soul or without sense or without a mind. This was an early shot across the bow — a signal that the church would not tolerate a Christology that compromised the completeness of Christ's humanity.¹⁶

The Council of Rome (377): Under Pope Damasus, this council explicitly condemned Apollinarianism by name and affirmed that Christ assumed a complete human nature, including a human rational soul. The Roman church made clear that any denial of Christ's human mind was incompatible with the faith.¹⁷

The First Council of Constantinople (381): This is the second ecumenical council, and it is the council that formally and definitively condemned Apollinarianism as a heresy. Constantinople I affirmed and expanded the Nicene Creed, addressed the Pneumatomachians (who denied the deity of the Holy Spirit), and condemned Apollinarianism. The council's inclusion of Apollinarianism in its list of condemned heresies placed this view definitively outside the bounds of orthodox Christianity. From this point forward, no one could affirm the Nicene faith and deny Christ's human soul.¹⁸

The Council of Chalcedon (451): As already noted, Chalcedon's Definition explicitly described Christ as "truly man, of a rational soul and body." The phrase was a direct and intentional repudiation of Apollinarianism. By specifying "rational soul" (psychē logikē, ψυχὴ λογική) as a constituent of Christ's human nature, the council left no room for any view that eliminates Christ's human mind.¹⁹

The Second Council of Constantinople (553): This fifth ecumenical council reinforced and developed the Chalcedonian framework. Constantinople II is especially important for our purposes because it includes explicit anathemas — formal condemnations — against anyone who denies that Christ has a human rational soul. The council addressed various Christological errors and made crystal clear that the union of the divine Word with human nature includes a genuine human intellect. As Timothy Pawl notes, the council's language makes it "difficult to see how, given the teachings of Conciliar Christology, one could make sense of the Word playing the role of Christ's soul."²⁰ Constantinople II stated that the Word is "hypostatically united to a composite that has as a part" both a rational soul and flesh — and this is what the Word assumed. Any view that removes the human soul from this composite falls under the council's condemnation.

Five major councils. Nearly two centuries of repeated condemnation. Let the weight of that sink in. The church did not address this question once and move on. It returned to it again and again, reinforcing the same verdict from different angles, in different contexts, across different regions of the Christian world. The message is unmistakable: Christ's possession of a human rational soul is non-negotiable. It is not an optional philosophical opinion. It is a foundational element of orthodox Christology, embedded in the creeds and the conciliar definitions that define the Christian faith.

Apollinarianism's Deeper Problems: Wilkinson's Three-Point Critique

Michael Wilkinson, in his groundbreaking work Crowned with Glory and Honor, develops a systematic three-point critique of Apollinarianism that goes beyond the soteriological and anthropological arguments we have already examined. His analysis helps us see why the Word-flesh paradigm is so deeply problematic — and why these same problems apply with equal force to modern physicalism.

First, Apollinarianism produces a deficient Christology by conforming it to a preconceived anthropology. Notice what Apollinarius did: he started with a theory of human nature (the tripartite body-soul-nous framework) and then forced the Incarnation to fit that theory. His anthropology drove his Christology, not the other way around. But as Wilkinson argues throughout his book, the proper theological method goes in the opposite direction. We should let Christ define what human nature is, not force Christ to fit our prior assumptions about human nature. When we start with Christ — the man par excellence, the perfect revelation of what it means to be human — we see that complete human nature includes both a body and a rational soul. The Incarnation reveals human nature; human nature does not constrain the Incarnation.²¹

This methodological insight is directly relevant to the physicalism debate. Physicalism, like Apollinarianism, starts with a prior commitment about human nature — in this case, the commitment that human beings are purely physical organisms — and then forces Christology to conform to that commitment. If humans have no soul, then Christ has no soul. But Wilkinson's point is that the direction should be reversed. If Christ's human nature includes a rational soul (as the councils insist), then human nature includes a rational soul. Christology should norm anthropology, not the reverse. We will return to this critical point shortly.

Second, Apollinarianism disorders Christology by constraining it to the ontology of preconceived anthropology. The Nicene tradition developed a careful distinction between hypostasis (ὑπόστασις, "person" — the individual subsisting subject, the "who") and ousia/physis (οὐσία/φύσις, "nature/essence" — the kind of thing something is, the "what"). This distinction was essential for the doctrine of the Trinity: one ousia, three hypostases. And it was equally essential for Christology: one hypostasis (the Son), two physeis (divine nature and human nature).

But Apollinarianism collapsed this distinction. In Apollinarius's scheme, the one composite Christ — the Word-flesh unity — functions as both the nature and the person simultaneously. The hypostasis is no longer the eternal Son who assumes a human nature; it becomes a new composite entity formed by the union of the Logos and flesh. As Wilkinson explains, without hypostasis and ousia functioning as distinct ontological categories, the Word-flesh incarnation "cannot identify the who and the what of Christ, and it struggles to distinguish what is divine and what is human in Christ."²² The ontological framework breaks down, and with it, the capacity to make the affirmations that orthodox Christology requires.

Third, Apollinarianism creates ontological confusion in the church's confession of both Christ and the Trinity. If the composite Christ is a single physis/hypostasis in which the Logos is the animating mind, then the divine Son — who is a hypostasis in the Trinity — has been replaced by a new kind of entity. The eternal Son cannot remain a divine hypostasis in the Godhead if He has become a composite part of a new hypostasis called "Christ." And since each self-directing nous in Apollinarius's system constitutes its own being, the result is a multiplication problem: God would seem to have two Sons — one eternal, one incarnate. This is precisely the kind of theological catastrophe that the councils worked so hard to prevent.²³

Wilkinson's conclusion captures the matter perfectly. The Word-flesh paradigm is "incompatible with a biblical and deeply coherent Christology because it cannot make the necessary person-nature distinction." The incarnate Son's identity as the eternal Son of the Trinity requires that the person-nature framework remain intact — and Apollinarianism destroys it.²⁴

Loke's Analysis: Apollinarianism and the Divine Preconscious Model

Andrew Loke, in his important work A Kryptic Model of the Incarnation, discusses Apollinarianism in the context of developing his own Divine Preconscious Model (DPM). Loke's analysis is helpful because it shows how his preferred Christological model avoids Apollinarianism while still maintaining the unity of Christ's person — the very concern that drove Apollinarius in the first place.

Loke observes that the key objections raised against Apollinarianism by the church fathers were several: it was virtually docetic (if Christ lacked a human mind and will, it is absurd to call Him a man at all); the rejection of normal human psychology clashes with the Gospel picture of a Savior who underwent all sorts of human experiences; and it failed to meet the essential conditions of redemption, since the rational soul — the seat of sin and moral choice — is the part most in need of redemption.²⁵

Loke's own model addresses Apollinarius's original concern — the unity of Christ's person — without sacrificing the completeness of His humanity. On the DPM, Christ has a genuine human soul, with human properties of consciousness and a human preconscious, that were created at the Incarnation. The divine properties (omniscience, omnipotence, omnipresence) were not surrendered but were held at a "preconscious" level — present but not constantly flooding Christ's waking human awareness. Christ has one consciousness with two aspects, divine and human, and a genuine human mind that could grow in knowledge and wisdom, just as any human child does. This is clearly not Apollinarian, because it affirms a created human mind alongside the divine nature.²⁶

Importantly, Loke notes that some other proposals — such as William Lane Craig's self-described "reformulation of Apollinarianism," in which the Logos contains perfect human personhood archetypically and brings all necessary human properties to the assumed body — face the same objections that troubled the original Apollinarianism. If Christ's human mind is not a created substance distinct from the divine Logos, then the question arises whether Christ truly has a human psychology, a human will, and a genuine human inner life. And if He does not, then Gregory's axiom applies with full force: what is not assumed is not healed.²⁷

Loke also raises a critical point about the intermediate state — the period between Christ's death and resurrection (the triduum mortis, the "three days of death"). On proposals like Erickson's and Craig's, which do not clearly affirm a human mind distinct from the divine nature, it is unclear whether Jesus remained truly human in the intermediate state. Did He simply become God simpliciter (God without any human nature) when His body died? And if so, did He then "re-incarnate" at the resurrection? Loke's DPM avoids this problem because it affirms that Christ's human soul — with its human properties of consciousness and human preconscious — continued to exist after His bodily death. He remained truly God and truly human even in the intermediate state.²⁸

This point about the intermediate state is directly relevant to the physicalism debate, which we will address fully in Chapter 21. For now, let us simply note the connection: any Christological model that eliminates Christ's human soul creates a devastating problem at the cross. On such a model, when Jesus died, there was no human soul to survive. His humanity simply ceased. And that is a Christological catastrophe — a dissolution of the hypostatic union that the councils explicitly forbade.

Crisp on the Nature of Christ's Humanity: Concrete Nature and Three-Part Christology

Oliver Crisp's treatment in Divinity and Humanity provides further philosophical clarity on why Christ must have a human soul and why Apollinarianism is untenable. Crisp examines the various ways one might conceive of Christ's human nature — the abstract nature view (Christ's human nature is a set of properties) versus the concrete nature view (Christ's human nature is a concrete particular, a body-soul composite) — and evaluates which views are theologically orthodox.

Crisp observes that a two-part concrete-nature Christology (the Word + a human body, with no distinct human soul) is "straightforwardly Apollinarian." If Christ's human nature is a concrete particular consisting only of a body, with the Word taking the place of the soul, then Christ simply lacks a human soul. This is exactly what the councils condemned.²⁹

Crisp's preference — which I share — is for a concrete-nature view combined with a three-part Christology: the divine Word, a human body, and a human soul distinct from the divine nature. This three-part structure avoids Apollinarianism (Christ has a genuine human soul), avoids Nestorianism (the human soul is not a separate person but is anhypostatic — it has no independent personal existence apart from the Son), and is consistent with dyothelitism (Christ has two wills — a divine will and a human will — because the human soul is the seat of the human will).³⁰

Crisp also argues — and I find this argument compelling — that if we accept the Chalcedonian definition, we should also accept the dyothelitism of Constantinople III (681), which affirmed that Christ has two wills. And two wills require two distinct centers of volitional activity — a divine will in the divine nature and a human will in the human soul. If Christ has no human soul, He has no human will. And if He has no human will, He is monothelite (possessing only one will) — which is itself a condemned heresy. The logic runs in a chain: deny the human soul, and you deny the human will; deny the human will, and you fall into monothelitism; and monothelitism was condemned at Constantinople III.³¹

Crisp concludes that "if Christ had no distinct human will he was not fully human. And, like most of the Fathers and the medieval schoolmen, I take it that a human nature is not fundamentally a property, but a concrete particular composed of a human body and a distinct soul."³² I could not agree more. This is the tradition's consistent witness, and it is the position that best accounts for everything Scripture and the councils teach about who Christ is.

The Critical Parallel to Modern Physicalism

We have now traced the Apollinarian controversy in detail — Apollinarius's view, the church's response, and the conciliar condemnations. It is time to draw the parallel that lies at the heart of this chapter — and at the heart of this entire book. I want to argue that modern Christian physicalism, when applied to Christology, produces the very same structural problem that Apollinarianism produced. The routes are different, but the destination is identical: Christ lacks an immaterial human soul.

Let me state the parallel as clearly as I can, and then I will develop it carefully and fairly.

Apollinarianism denies that Christ has a human rational soul. The divine Logos replaces it.

Physicalism denies that any human being has an immaterial soul. There is no such thing as a soul, for Christ or for anyone else.

The result is the same: Christ lacks an immaterial human soul.

The councils condemned the first view. I believe that the same logic condemns the second.

Now, I want to be careful and fair here, because this is a serious charge, and physicalist scholars are serious Christians who do not intend to be Apollinarian. Let me acknowledge several important things before developing the argument.

First, I acknowledge that physicalists have good intentions. Christian physicalists like Nancey Murphy, Joel Green, and Kevin Corcoran are not trying to undermine the faith. They believe they are affirming Christ's complete humanity by affirming His complete physical body. They think that a physicalist account of human nature is more consistent with the biblical witness (a claim I disagree with, as argued in Chapters 3 and 4) and more consistent with modern science (a claim that is debatable, as argued in Chapters 4 and 5). They are not attacking Christ. They are trying to understand Him. I respect their intentions, even as I believe their position has devastating Christological consequences.

Second, I acknowledge that the historical context is different. Apollinarius denied the soul in Christ specifically — he believed that other human beings have rational souls, but Christ's was replaced by the Logos. Physicalists deny the soul in all humans — they do not single out Christ. So the route is different. Apollinarius was making a Christological move; physicalists are making an anthropological move that has Christological consequences.

Third, I acknowledge that physicalists do not consider themselves Apollinarian. They believe that by affirming Christ's complete physical body — including His brain and all its functions — they are affirming His complete humanity. On their view, a "rational soul" is simply the functioning of a sufficiently complex brain, and Christ certainly had that. So they would say that they affirm everything Chalcedon requires — Christ is truly man, with a rational soul and body — they just interpret "rational soul" as a reference to the higher-order capacities of a physical brain, not as a reference to an immaterial substance.

I understand these points, and I take them seriously. But I do not think they get physicalism off the hook. Here is why.

The Councils Meant Something Specific

When the Council of Chalcedon declared that Christ is "truly man, of a rational soul and body," the council fathers were not using the words "rational soul" as a metaphor for brain function. They were using the language of the anthropology they shared — an anthropology in which the "rational soul" (psychē logikē) is a genuine, distinct, ontological component of human nature, not merely a description of what a brain does. The entire Apollinarian controversy was premised on the understanding that the rational soul is something — a real aspect of human nature that can be either present or absent in a given being. Apollinarius denied it was present in Christ. The councils insisted it must be present. This debate only makes sense if the "rational soul" is a genuine ontological reality, not a functional description of brain activity.

Joshua Farris makes this point in his discussion of Chalcedonian Christology. The conciliar definition insists that Christ has a complete human nature, and a complete human nature was understood to include a body and a rational soul — not merely a body whose brain functions exhibit rational activity. If Apollinarianism is true, Farris notes, "then it seems to follow that Christ saves only a part of humanity: the bodily part of humanity."³³ The same applies to physicalism. If there is no soul — only a body — then Christ can only save the body. But the tradition has consistently affirmed that salvation addresses the whole person, body and soul.

To reinterpret "rational soul" as "brain function" is to empty the conciliar language of its original meaning. It is like reinterpreting the Nicene Creed's affirmation that the Son is homoousios (of the same substance) with the Father as meaning merely that the Son is "similar in function" to the Father. No — homoousios means something ontologically specific. And psychē logikē means something ontologically specific too. It refers to an immaterial rational soul — the very thing that Apollinarius denied and the councils insisted Christ must have.

The Structural Logic Is Identical

Regardless of the different routes by which Apollinarianism and physicalism arrive at their conclusions, the Christological result is structurally identical. On both views, Christ's human nature does not include an immaterial rational soul. And that is precisely what the councils condemned.

Consider the logic again:

The councils defined "complete human nature" as body + rational soul (not body alone).

Apollinarianism gives Christ a body but no human rational soul → incomplete human nature → condemned.

Physicalism says there is no such thing as a soul for anyone → Christ has a body but no immaterial rational soul → incomplete human nature (by the council's definition) → same structural result.

The question is not what physicalists intend. The question is what their position logically entails. And what it logically entails is that Christ lacks the very thing the councils insisted He must have. The fact that physicalists also deny the soul in all other humans does not help. If anything, it makes the problem worse — because now not only Christ but all human beings lack the component that the tradition has identified as essential to human nature.

The Physicalist's Response and Why It Falls Short

Physicalists are, of course, aware of this objection, and they have offered responses. The most common response is the one I mentioned above: they claim to affirm everything Chalcedon requires, because they interpret "rational soul" functionally rather than ontologically. On their view, having a "rational soul" simply means having the higher-order capacities associated with a sufficiently complex brain — capacities like reasoning, willing, emoting, and relating to God. Christ had a human brain; therefore, Christ had a "rational soul" in the relevant sense. Nothing is missing.

This response, while understandable, faces several serious problems.

First, as I have already argued, this interpretation empties the conciliar language of its original meaning. The council fathers were not functionalists about the soul. They believed the rational soul is a genuine ontological component of human nature — something real, something that can exist apart from the body (as in the intermediate state), something that is more than just what a brain does. To read physicalist assumptions back into the fourth- and fifth-century councils is anachronistic.

Second, this response does not address Gregory of Nazianzus's axiom. Gregory's argument is not merely that Christ must have the functions of a rational soul. It is that Christ must assume everything that needs to be redeemed. On substance dualism, the human soul is a genuine immaterial substance that is the seat of personal identity, moral agency, and relationship with God. It is the soul that sins, the soul that needs redemption, the soul that must be healed. If there is no soul — if all of this is just brain activity — then there is nothing for Christ to assume beyond a body. But the tradition has consistently taught that Christ assumed more than a body. He assumed a complete human nature — body and soul. On physicalism, there is no "more." There is only the body. And that, in Gregory's framework, means the most important part of us has not been assumed and therefore has not been healed.

Third, as Farris observes, there is a difference between a two-part materialist Christology and a three-part dualist Christology, and the difference has enormous consequences. On a materialist Christology, the Logos needs only to assume one part — a body — to become human. But this raises the question: can one construe a "rational soul" as merely a set of neural properties tied to a brain and still satisfy the requirements of Chalcedon? Farris notes that the "obvious challenge for a two-part materialist Christology comes from the doctrine of Christ's persistence upon somatic death. Upon Christ's human body dying, Christ would cease to be human."³⁴ Without a human soul, there is no human nature left after the body dies. The Incarnation is interrupted. The hypostatic union is dissolved. This is precisely the devastating triduum problem that we will address at length in Chapters 21 and 22.

Fourth, the physicalist response must reckon with the broader implications for other Christological commitments. If Christ has no immaterial soul, then His "human will" (affirmed at Constantinople III) is nothing more than neural activity in His brain. But can a pattern of neural firing constitute a genuine "will" in the theological sense the councils intended? The councils understood the will as a rational, moral faculty — the capacity to deliberate, choose, and act intentionally. Can a brain state deliberate? Can a neural event freely choose? On physicalism, these are either metaphors for physical processes or they are determined by prior physical causes. Either way, the rich theological content of the conciliar affirmations is hollowed out. This concern connects directly to the discussion of dyothelitism in Chapter 14 and the sinlessness problem addressed in Chapter 27.

Farris and the Christological Argument for Dualism

Joshua Farris, in his Introduction to Theological Anthropology, develops the Christological argument against physicalism with particular clarity. He notes that the Chalcedonian confession that Christ has a "rational soul" is not a peripheral detail but a central and deliberate affirmation. The framers of Chalcedon understood that Christ's human nature must be complete in order for the Incarnation to accomplish its salvific purpose. As Farris writes, Chalcedon's dual concern is both salvific and revelatory: "Christ reveals God's nature to humans, and Christ reveals humanity as God intended." These twin concerns of salvation and revelation are joined when we understand that Christ's full humanity is essential to both.³⁵

Farris explicitly draws the parallel between Apollinarianism and physicalism that I have been developing. On Apollinarianism, the Logos already had a mind, so all He needed to assume was a body. The result is that Christ saves only a part of humanity — the bodily part. Farris then notes that materialist Christologies face the same structural problem. On a materialist view, the Logos assumes a body (or a body whose brain gives rise to higher-order neural properties of consciousness), and this is supposed to satisfy Chalcedon's requirement for a "rational soul." But the conciliar language was designed to affirm more than brain function. It was designed to affirm that Christ has a genuine immaterial component to His humanity — a soul that can persist through death, that grounds His personal identity, and that is the seat of His human will and moral agency.³⁶

Farris also observes that some contemporary philosophers have tried to construct a physicalist Christology by arguing that the higher-order properties of a human brain can serve as a functional equivalent of the "rational soul." On this view, we have a two-part Christology: the Logos and a human body with its attendant neural properties. But Farris points out the fatal problem with this approach: "Upon Christ's human body dying, Christ would cease to be human. The concern that he persists raises significant worries about his representational work on behalf of humans during the intermediate state of disembodied existence. Without a human body, on a materialist account, there is no part that would sufficiently make Christ a human."³⁷ This is the triduum problem — and it is devastating for any physicalist Christology. A dualist account, by contrast, provides a human soul that persists through death and maintains Christ's humanity during the intermediate state.

The Holy Saturday Problem: A Preview

We will address the triduum problem — what happened to the Incarnation between Good Friday and Easter Sunday — at length in Chapters 21 and 22. But let me offer a brief preview here, because the Apollinarian parallel makes it unavoidable.

The chapter by James T. Turner Jr. in Christian Physicalism? on "Holy Saturday and Christian Theological Anthropology" explores this problem in detail. Turner examines three physicalist models for understanding Christ's intermediate state — gappy existence, alternate temporality, and immediate resurrection — and finds that each one faces serious difficulties in maintaining the theological principles that orthodox Christology requires. Turner notes that the "dogmatic teaching of the Catholic Nicene tradition reflects the collective agreement of theological authorities that affirm with one voice the doctrine of the soul (that is, as an immaterial substance, or something near it) that has the possibility of persisting disembodied during the interim state." This consensus is "buttressed by the belief that Christ persisted as a human on Holy Saturday."³⁸

The logic is simple. If physicalism is true, then when Christ died, His human nature ceased to exist (since, on physicalism, human nature just is the functioning physical body). The Son of God was no longer united to a human nature during the triduum. The Incarnation was interrupted. But the Chalcedonian Definition says the two natures are united "without separation." The Incarnation cannot be interrupted. Therefore, there must be something — a human soul — that survives death and maintains Christ's humanity during the triduum. On dualism, this is straightforward: Christ's human soul survived His bodily death and was active during the three days between crucifixion and resurrection (He "descended to the dead," as the creed says). On physicalism, there is no soul to survive, and the Incarnation simply lapses.

Turner concludes that "physicalist models require increasingly complex mechanisms to explain the theological principles connected to Christ's intermediate state on Holy Saturday," while dualist models have "a relatively straightforward way of explaining the continuity."³⁹ This is a devastating assessment, and it reinforces the Apollinarian parallel. Apollinarianism destroyed the completeness of Christ's humanity during His earthly life. Physicalism destroys the continuity of Christ's humanity at His death.

Wilkinson's "Chalcedonian Anthropology": Christology Norms Anthropology

Before we conclude, I want to return to one of the most important insights in this entire discussion — an insight developed most fully by Michael Wilkinson in Crowned with Glory and Honor. Wilkinson argues that the proper theological method is to let Christology norm anthropology, not the other way around. In other words, we should not start with our assumptions about what human beings are and then force Christ to fit those assumptions. Instead, we should start with what the church confesses about Christ — the man par excellence, the perfect revelation of true humanity — and let that confession inform our understanding of what human beings are.

Wilkinson calls this a "Chalcedonian anthropology." The Chalcedonian Definition tells us that Christ is "truly man, of a rational soul and body." If Christ's human nature consists of a rational soul and a body, then human nature consists of a rational soul and a body. If the perfect exemplar of humanity has both a body and a soul, then human beings have both a body and a soul. Christ does not merely illustrate human nature — He defines it.⁴⁰

This methodological principle has a directly negative implication for physicalism. If we take the Chalcedonian path — letting Christ define human nature — then physicalism is ruled out from the start. Christ's human nature includes a rational soul. Therefore, human nature includes a rational soul. And if human nature includes a rational soul, then physicalism (which denies the existence of the soul) is false. It is not just false as a philosophical theory about human nature. It is false as a theological claim about what it means to be human, because it contradicts what the church's highest Christological definitions tell us about the humanity of Christ.

As Wilkinson puts it, the incarnation of our Lord Jesus Christ gives us the man par excellence, which must govern how we define man par ordinaire. Normally, if we applied common dualist anthropology (in which the "person" is identified with either the entire existing individual or with the human soul) directly to Christ, we would risk either Nestorianism or Apollinarianism. Thus, the direction must be reversed: what should govern our thinking about humans is Christ's person-nature ontology, as defined by Chalcedon, which is then applied to us analogically.⁴¹

I find this argument deeply compelling, and I believe it cuts the ground out from under any attempt to marry physicalism with orthodox Christology. If Christ's human nature includes a soul, and Christ is the paradigm of what it means to be human, then human nature includes a soul. Physicalism denies this. Therefore, physicalism contradicts what Christ reveals about our nature. The argument is clean, the logic is tight, and the conclusion is clear.

The "Two Sons" Worry and Physicalist Counter-Arguments

In fairness, we should note that some physicalists have tried to turn the tables on dualists. In the volume Christian Physicalism?, one chapter on "Physicalist Christology and the Two Sons Worry" observes that it is not hard for a physicalist to construct a "Two Sons Worry" argument against the dualist who affirms the standard three-part dyothelite Christology. On such a Christology, God the Son is a divine mind with a will, and God the Son assumes a human soul and body. This human soul has its own distinct will. Since the dualist affirms that a person is an immaterial substance with the capacity to think and perform free actions, and since there are two such immaterial substances in Christ (the divine nature and the human soul), it seems — so the argument goes — that there are two persons in Christ. Two sons.⁴²

The physicalist then argues that her view fits better with ecumenical Christology because on a physicalist Christology, the Son does not assume a human soul. Instead, the Son becomes identical to (or uniquely related to) a human body. There should be no worry about having two thinkers in Christ.⁴³

This is a clever argument, and I take it seriously. But it does not succeed, for several reasons.

First, the "Two Sons Worry" has well-established solutions within the dualist tradition. The doctrine of anhypostasia and enhypostasia (which will be treated fully in Chapter 19) addresses this directly. Christ's human soul is anhypostatic — it has no independent personal existence of its own apart from the Son's assumption of it. It never existed as its own person. It was created in, by, and for the Son at the moment of the Incarnation. It is enhypostatic — it finds its personal subsistence in the hypostasis of the Son. So while Christ has a human soul with its own rational capacities and will, this soul is not a separate person. It is the human nature of the one divine Person. The "Two Sons Worry" arises only if one assumes that every immaterial substance with rational capacities is automatically a person — and that is precisely what the anhypostasia/enhypostasia doctrine denies.⁴⁴

Second, the physicalist's proposed solution — eliminating the human soul to solve the "Two Sons" problem — creates far worse problems than it solves. It "solves" the unity of Christ's person by destroying the completeness of His human nature. It is like solving a headache by cutting off one's head. Yes, the headache is gone — but so is everything else. The physicalist avoids the "Two Sons Worry" but falls straight into Apollinarianism (Christ lacks a human soul), the triduum problem (the Incarnation dissolves at death), the monothelitism problem (Christ has no genuine human will), and the soteriological problem (the unassumed is the unhealed). These are not minor difficulties. They are Christological catastrophes.

Third, as Loke demonstrates with his Divine Preconscious Model, it is entirely possible to maintain a three-part Christology (divine nature + human soul + human body) while also maintaining the genuine unity of Christ's person through the one-consciousness model. On the DPM, Christ has one consciousness with two aspects (divine and human), not two separate consciousnesses. The unity of the person is preserved without sacrificing the completeness of the human nature. This shows that the "Two Sons Worry" is not an inevitable consequence of dualist Christology — it is a consequence of a particular way of understanding dualist Christology that Loke's model avoids.⁴⁵

Pawl on the Conciliar Rejection of Apollinarianism

Timothy Pawl, in his rigorous philosophical defense of conciliar Christology, addresses the Apollinarian question with characteristic clarity and precision. Pawl notes that the councils' repeated insistence that Christ's human nature includes a rational soul makes it "difficult to see how, given the teachings of Conciliar Christology, one could make sense of the Word playing the role of Christ's soul." If the Word were to play the role of the soul, and if the Word were also hypostatically united to flesh enlivened with a rational soul (as the councils affirm), then the Word would be united to a composite that has itself as a part — a metaphysical puzzle that borders on incoherence.⁴⁶

Pawl observes that Apollinarius himself would have denied this characterization. On Apollinarius's view, the thing assumed was not a composite of a human soul and flesh but just the flesh. So there is only one uniting, not a doubled hypostatic union. But, as Pawl notes, "his theory removes the difficulty of understanding a doubled hypostatic union, but only at the cost of denying what the councils say multiple times over: that the non-divine relatum of the union includes a rational soul."⁴⁷

This is exactly the trade-off that physicalism makes as well. Physicalism simplifies the metaphysics of the Incarnation by eliminating one component — the immaterial soul. But it does so at the cost of denying what the councils explicitly and repeatedly affirm: that Christ's human nature includes a rational soul. The simplification comes at too high a theological price.

Pawl also draws attention to the historical observation made by Herbert Relton: it was the acceptance of what Relton calls the "Person-Nature Conditional" — the assumption that a complete nature necessarily includes a person — that drove Apollinarius to deny Christ a human soul. Apollinarius feared that a complete human nature would entail a complete human person, resulting in two persons in Christ. This same fear later produced both Nestorianism (which accepted two natures but ended up with two persons) and Eutychianism (which merged the natures to secure one person). Apollinarianism, Nestorianism, and Eutychianism are all different but equally flawed responses to the same underlying difficulty: how to hold together one person and two complete natures.⁴⁸

The councils' answer was neither to diminish the humanity (Apollinarianism), nor to divide the person (Nestorianism), nor to merge the natures (Eutychianism), but to hold all three affirmations simultaneously: one person, two complete natures, united without confusion, change, division, or separation. This is the Chalcedonian settlement. And it requires that Christ have a complete human nature — including an immaterial rational soul.

What the Physicalist Cannot Have

Let me summarize what the physicalist cannot have if the argument of this chapter is correct.

The physicalist cannot have a Christology that satisfies the councils. The councils defined "complete human nature" as body + rational soul. Physicalism eliminates the rational soul from its ontology. Therefore, the physicalist's Christ does not have a complete human nature as the councils defined it.

The physicalist cannot satisfy Gregory's axiom. If there is no immaterial soul, then Christ did not assume an immaterial soul. And what is not assumed is not healed. On substance dualism, the human soul is a genuine part of our nature that needs redemption. On physicalism, there is nothing beyond the body to assume. Gregory's axiom becomes vacuous — not because the principle is wrong, but because physicalism has eliminated the very thing the principle demands be assumed.

The physicalist cannot maintain the Incarnation through death. If human nature is purely physical, then when Christ died, His human nature ceased to function. There is no soul to survive, no soul to maintain the union, no soul to descend to the dead. The Incarnation lapses at the cross — "without separation" notwithstanding (as we will explore in full in Chapters 21 and 22).

The physicalist cannot give Christ a genuine human will in the conciliar sense. If there is no soul, then the "human will" is merely brain activity. But the councils understood the will as a genuine faculty of the soul — a rational, moral capacity for deliberation and free choice (as we will explore in Chapters 13 and 14).

The physicalist cannot maintain a consistent account of Christ's persistent humanity. Christ ascended bodily and remains incarnate forever (as we will address in Chapter 26). On physicalism, Christ's "human nature" is entirely constituted by His physical body. But what does it mean for a purely physical human organism to be "seated at the right hand of the Father"? On dualism, Christ's human soul remains united to both His divine nature and His glorified body, providing a coherent account of the ongoing Incarnation.

The cumulative force of these problems is, I believe, overwhelming. Physicalism simply cannot support the Christological framework that the church has confessed for seventeen centuries. And the root cause of every one of these problems is the same: physicalism eliminates the human soul. It is the same root cause that made Apollinarianism unacceptable. The heresy has returned in a new form.

Conclusion: The Church Has Already Spoken

The early church fought the battle over Christ's human soul in the fourth century, and the verdict was unequivocal. Christ must have a complete human nature — body and rational soul. This is not a peripheral philosophical opinion. It is a dogmatic definition of the ecumenical councils, embedded in the creed that every Christian confesses. Apollinarianism was condemned not once but five times, over nearly two centuries, by councils representing the entire Christian world. The church understood that the completeness of Christ's humanity is essential to the completeness of our salvation. What is not assumed is not healed.

I believe that modern physicalism, when applied to Christ's human nature, reproduces the structural error that the church already condemned. The routes are different — Apollinarius replaced the soul with the Logos; physicalism eliminates the soul entirely — but the Christological destination is the same. Christ is left without an immaterial human soul. And the councils have declared, with the full weight of their authority, that this is not an acceptable position for any Christian to hold.

Physicalist scholars who embrace these views are, in my judgment, sincere Christians who are unaware of (or who underestimate) the devastating Christological consequences of their position. They are not intentionally Apollinarian. But intention is not the issue. The issue is logical consequence. And the logical consequence of denying the human soul — for Christ as for all human beings — is an incomplete human nature in the one Person who, above all others, must have a complete one.

The Word became flesh — yes. But He also assumed a human soul. He entered into the full depth of our condition — body and soul, outer and inner, physical and spiritual. He took on everything we are so that He could redeem everything we are. That is the glory of the Incarnation. And it is a glory that physicalism, for all its good intentions, cannot preserve.

In the next chapter, we will continue our study of the conciliar Christological framework by examining the Fifth Ecumenical Council (Constantinople II, 553) and the Sixth Ecumenical Council (Constantinople III, 681), which completed the conciliar definitions by affirming Christ's genuine human will — a will that, as we will see, presupposes the very human soul whose existence we have defended here.

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