In a prior article (here), I explored how the second-century work the Epistle to Diognetus clearly affirmed the full divinity of Jesus–a doctrine that some say did not come around until the fourth century. I continue this theme by exploring yet another doctrine that some suggest is a late invention: substitutionary atonement.

The average internet-level narrative goes something like this: the earliest Christians had no clear understanding for why Jesus died on the cross and what it accomplished. The idea of a substitutionary atonement is a late invention designed to retroactively explain the (otherwise embarrassing) death of Jesus. In fact, it was not until Anselm’s Cur Deus Homo (Why the God-Man?) in the middle ages that someone came up with the idea that Jesus died in place of sinners.

Of course, such a narrative can be readily refuted just examining the writings of the New Testament itself–particularly the letters of Paul. However, it is also worth noting that this view was held by some of the earliest Christian writers; in this case, by the author of the Epistle to Diognetus in the early second century. Here are some excerpts from the author that affirm key aspects of substitutionary atonement:

The Seriousness of Sin

The author writes:

And when we had demonstrated that we were powerless to enter the kingdom of God on our own, were were enabled by the power of God. For our unrighteous way of life came to fruition and it became perfectly clear that it could expect only punishment and death as its ultimate reward (9.1-2).

Here is a clear affirmation of human inability to save ourselves (akin to total depravity), and a full acknowledgement that sin deserves the ultimate penalty of death.

The Grace and love of God toward Sinners

The author writes:

But then, when the time arrived that God planned to reveal at last his goodness and power (Oh the supreme beneficence and love of God!), he did not hate us, destroy us, or hold a grudge against us (9.2).

God’s response to our sin, though deserving of death, is not to bring judgment but to show mercy.

Christ Bore Our Sins on Himself

Here is where we get to the crux of substitutionary atonement:

But [God] was patient, he bore with us, and out of pity for us took our sins upon himself. He gave up his own Son as a ransom for us, the holy one for the lawless, the innocent one for the wicked, the righteous one for the unrighteous, the imperishable one for the perishable, the immortal one for the mortal. (9.2).

Here is a remarkable passage. Undoubtedly, the author views the work of Christ on the cross as an exchange, a swapping, of the righteous for the unrighteous, that we might be saved. And he says plainly that Christ “took our sins upon himself.” He stood in our place and bore God’s wrath for us.

Christ’s Righteousness Covers Us

Incredibly, the author even seems to affirm what Reformed folks refer to as the doctrine of imputation. This doctrine says that our justification is not only about having our sins taken away, but having Christ’s positive righteousness cover us. The author of the Epistle to Diognetus states:

For what else could hide our sins but the righteousness of that one? How could we who were lawless and impious be made upright except by the son of God alone? Oh the sweet exchange!…That the lawless deeds of many should be hidden by the one who was upright, and the righteousness of one should make upright the many who were lawless!

This is a significant passage because it doesn’t dwell on just our sins being taken away, but dwells substantively and primarily on the righteousness of Christ. And what does that righteousness do? It hides our sins. And it “makes upright” the lawless. And this happens in a “sweet exchange.” If we are looking for an ancient writer who describes the doctrine of the imputation of Christ’s righteousness, this comes awfully close.

In sum, the Epistle to Diognetus shows that the doctrine of the substitutionary atonement, and also the imputation of Christ’s righteousness, are not late inventions, but were present very early in the history of Christianity. Did some Christian groups hold other views of such matters? Sure. But, the continuity between the teachings of this epistle, and the writings of Paul himself (see especially Romans 5), make it evident that the substitutionary atonement/imputation view goes back very early indeed.