On the Incarnation

Overview

About ninety pages, written by Athanasius of Alexandria around 318 CE, when he was probably still in his twenties, well before he became bishop of Alexandria and long before he spent decades of his episcopate exiled repeatedly for refusing to compromise on the doctrine this treatise defends. It is generally read as a companion piece to an earlier work, Against the Gentiles, which argues against pagan idolatry and polytheism; where that treatise clears the ground, this one builds directly on it, asking why, given everything already established about the true God, that God specifically had to become human.

Athanasius wrote well before the Council of Nicaea in 325, which he would later attend as a young deacon and whose formula, that the Son is of one substance with the Father, he would spend the rest of his long and turbulent career defending against a series of emperors and rival bishops who favored the Arian position that the Son was a created being, exalted but not fully and eternally divine. This early treatise does not engage that later controversy by name, since it largely predates it, but its argument, that only the Word who is truly God and truly the source of all created life could reverse humanity’s slide back toward nonexistence, supplies much of the theological logic that made the fully divine status of Christ seem, to Athanasius and to the tradition that followed him, not a technical dispute but the very thing salvation depended on.

The treatise had an unusual afterlife in English letters: C. S. Lewis wrote an introduction to a twentieth-century translation, in which he urged readers to go directly to old books like this one rather than settling for modern summaries of them, on the ground that every age, including our own, has its own characteristic blind spots that only genuinely old books can correct.

The argument

Why humanity was made, and how it fell toward nothing. Athanasius begins from the doctrine of creation out of nothing, out of ouk onton, and draws a consequence from it that shapes everything else in the treatise: since human beings were made from nothing, their natural tendency, apart from some further gift sustaining them, is to slide back toward the nonexistence they came from. To prevent this, God did not merely create humanity and leave it to its own resources; he made human beings in the image of his own Word and gave them, by grace, a share in the Word’s imperishable life, so that as long as they remained in that relationship of dependence and likeness, they would not undergo the natural corruption otherwise proper to a creature made from nothing.

Sin, on this account, is fundamentally a turning away from that sustaining relationship, a turning of attention and desire from the eternal Word toward the created, temporal things nearer at hand. And the consequence of that turning is not an arbitrary penalty imposed from outside but something closer to a natural forfeiture: cut off, by their own choice, from the Word who alone kept them from reverting to nothing, human beings began sliding back toward the corruption and dissolution that is simply what happens to a creature made from nothing once nothing sustains it otherwise.

Why repentance could not be enough. Athanasius considers, and rejects, the possibility that a change of heart alone, repentance, might have been sufficient to reverse this. His argument is precise: repentance can restore right belief and right desire going forward, but it cannot undo a corruption that has already, as a matter of fact, been loosed into human nature. A change of mind addresses guilt; it does not, on its own, reverse an already-occurring process of decay any more than telling a person newly to want health reverses an illness already advanced in the body. Something more than a change of disposition was required, some remedy that could act directly on the corruption itself.

God’s dilemma. This sets up the treatise’s central argument, framed not as a conflict between divine justice and divine mercy, the way later theology sometimes presents it, but as a dilemma about what would be fitting for God given who God already is. It would be unfitting, Athanasius argues, for God simply to let his own work, humanity made in his Word’s image, be entirely undone by corruption, since this would call into question the point of having created humanity at all. But it would be equally unfitting for God to disregard or reverse by bare decree the consequence, death, that he had truly attached to sin, since this would make God inconsistent with his own prior word.

The solution Athanasius proposes is that only the Word himself, by taking on a genuine, mortal human body, could resolve both concerns simultaneously: by assuming a body capable of death, the Word could pay, within that body, the debt of death owed by human nature generally, satisfying what had truly been decreed, while at the same time, because it was the Word himself, the source of imperishable life, who was now united to that body, the Word could break death’s ultimate hold and render the body, and through it human nature generally, incorruptible once more.

Death defeated from inside. Athanasius describes the crucifixion specifically, rather than some other kind of death, as fitting for this purpose in a further, particular way: it was a death undergone publicly, decisively, and completed rather than merely threatened, a death that could be witnessed by all and that could not be mistaken for mere apparent death or escape, which matters to Athanasius’s larger argument that the resurrection which follows is a real victory over a real and completed death, not a trick played on an illusory one. The Word takes death upon himself specifically to exhaust and defeat it, offering himself on behalf of all so that, having genuinely died and genuinely risen, human nature as a whole, now reunited with its true source of life in his person, is no longer bound to slide back toward the nothing it came from.

Answering Jewish and Greek objections. The treatise’s later sections turn from setting out the positive doctrine to defending it against two sets of objectors Athanasius expects his readers to encounter. Against Jewish objectors who deny that the Messiah could suffer and die in this way, he argues at length from Hebrew prophetic texts that a suffering, dying and rising Messiah was foretold all along, and that the specific circumstances of Christ’s death fulfill those prophecies in detail. Against Greek, meaning pagan philosophical, objectors who find the idea of God taking on a body beneath the dignity of true divinity, he argues from what he presents as an observable, ongoing historical fact: the rapid and visible collapse of idolatry and pagan religious practice across the Mediterranean world in the wake of Christianity’s spread, which he takes as evidence, available to any observer regardless of prior belief, that something genuinely powerful has actually occurred in history rather than remaining a merely private or philosophical claim.

How to read it

Read the first several sections on creation from nothing and the nature of the fall carefully; the entire logical structure of the argument that follows, why repentance is insufficient and why only the Word’s own death and resurrection could resolve the problem, depends on accepting this specific account of what sin actually did to human nature.

Notice that Athanasius frames the central dilemma as a question of what is fitting for God, rather than as a straightforward conflict between justice demanding punishment and love wanting to forgive. This framing, sometimes obscured in later, more juridically flavored accounts of atonement, is distinctive to this early treatise and worth holding onto as you read.

Pay attention to why the specific manner of Christ’s death, public, decisive, unmistakably real and complete, matters so much to Athanasius’s argument. The logic of defeating death from within requires that the death actually undergone be genuine and total, not merely apparent, and Athanasius spends real effort establishing this.

Read the later sections on prophecy and the collapse of idolatry as historically specific arguments addressed to Athanasius’s actual fourth-century audience and their actual objections, rather than as philosophical proofs meant to hold for every age. Doing so makes clear both what kind of evidence Athanasius thought would be persuasive to his contemporaries and how different that evidentiary landscape is from a modern reader’s own.

Read C. S. Lewis’s introduction, widely printed alongside the older translation, for his argument about why reading old books like this one directly, rather than only reading modern summaries and discussions of them, corrects blind spots that are otherwise invisible from within any single era, including our own.

Read this treatise alongside Augustine’s Confessions or City of God to see how differently two major early Christian thinkers, writing in different languages and intellectual traditions within a few generations of each other, work out related questions about sin, grace and what salvation actually requires.

Questions it raises

• Is Athanasius’s account of death as a natural reversion toward nonexistence, rather than primarily an externally imposed punishment, a more or less troubling picture of the human condition than more juridical accounts of sin and its consequences?
• Does the argument that repentance alone cannot undo already-loosed corruption hold up, or does it depend on treating moral and ontological categories, guilt and physical decay, as more tightly linked than they need to be?
• Athanasius frames God’s dilemma as a matter of consistency and fittingness rather than as a conflict between justice and mercy. Does this framing genuinely avoid the puzzles that arise when justice and mercy are set directly against each other?
• What work is being done by the specific claim that the Word must take on a body capable of death in order to die in it? Could some other kind of divine action have accomplished the same defeat of corruption?
• How persuasive, to a modern reader, are Athanasius’s arguments from fulfilled prophecy and from the historical collapse of idolatry, compared to how persuasive they were evidently intended to be to his fourth-century audience?
• If human nature was corrupted by a turning away from the Word, does uniting the Word to one human body in the Incarnation actually restore all of human nature, or only the specific body the Word assumed? What is Athanasius’s answer, and is it convincing?