What theory of the atonement did Thomas teach?

Given that penal substitutionary atonement is sometimes thought of as a Protestant doctrine (although Protestants of the past have not necessarily viewed the matter this way; Rev. William Symington called it ‘the catholic view’), [1] it is interesting to note that Thomas, considered by many to be the great doctor of the Roman Catholic Church, taught a view of the atonement properly described as penal-substitutionary.

We define penal substitutionary atonement as the doctrine that Christ, in his death on the cross, bore punishments due to us, for our sin, in our place, and that in so doing, he attained for us the forgiveness of sins.

Each of these elements is clearly present in Thomas’s statements concerning the atonement.

According to Thomas, commenting on Isaiah 53 (Isaiah.C53.n960),
“Second, as to his exposed infirmity, he sets out the sign of his infirmity: ‘truly,’ as true man, ‘he has borne,’ suffered, ‘our infirmities,’ infirmities, such as hunger and thirst, ‘and carried our sorrows,’ of sense, in suffering and sadness; or, ‘our infirmities,’ our sins, he has taken from us; or in our place, he has suffered punishments: ‘he bore our sins in his body upon the tree’ (1 Pet 2:24).‘”

The words ‘he has taken from us our sins…’ ‘he has suffered punishments in our place’ are clear examples of penal substitutionary language.

Thomas goes on to example that this atonement for Christ has reconciled us to God (Ibid. no.965):

“Second, he shows the consequent usefulness in the reconciliation of peace: ‘the chastisement of our peace,’ that is, he endured the chastisement of correction for us, and through this peace we have access to God: for if, when we were enemies, we were reconciled to God by the death of his Son (Rom 5:10); and in the restoration of broken health: ‘by his bruises,’ which he had from the scourges, ‘we are healed:’ ‘by whose stripes you were healed’ (1 Pet 2:24); ‘who forgives all your iniquities: who heals all your diseases’ (Ps 102[103]:3).”

Moreover, critical for distinguishing Penal Substitution from the so-called Ransom Theory of the atonement (‘Christ purchased us from the devil’) is the point that Christ’s sacrifice was offered to the Father. Thomas also clearly teaches this point:

“’He was offered.’ Here he shows his meekness in suffering.

And first, he sets out the meekness itself, and first, as to his voluntary offering of himself: ‘he was offered,’ to God the Father as a victim for us, because it was his own will: ‘I will freely sacrifice to you.’ (Ps 53:8[54:6])”

Thomas repeats many of the same ideas in his Commentary on Galatians, 3:13-14. he says,
“Then when he says, ‘being made a curse for us,’ he sets forth the manner of the deliverance. Here it should be noted that a curse is that which is said as an evil. Now it is according to two kinds of evil that there can be two kinds of curse, namely, the curse of guilt and the curse of punishment. And with respect to each this passage can be read, namely, ‘he was made a curse for us.’
First of all with respect to the evil of guilt, for Christ redeemed us from the evil of guilt. Hence, just as in dying he redeemed us from death, so he redeemed us from the evil of guilt by being made a curse, i.e., of guilt; not that there was really any sin in him, for ‘he did not sin, neither was guile found in his mouth’ (1 Pet 2:22), but only according to the opinion of men and particularly the Jews who regarded him as a sinner: ‘if he were not a malefactor, we would not have delivered him up to you’ (John 18:30). Hence it is said of him, ‘him who knew no sin he has made sin for us’ (2 Cor 5:21)…
Second, it is explained with respect to the evil of punishment. For Christ freed us from punishment by enduring our punishment and our death which came upon us from the very curse of sin. Therefore, inasmuch as he endured this curse of sin by dying for us, he is said to have been made a curse for us. This is similar to what is said in Romans: ‘God sent his own Son in the likeness of sinful flesh and of sin’ (Rom 8:3), i.e., of mortal sin. ‘Him who knew no sin,’ namely, Christ, who committed no sin, God (namely, the Father) ‘has made sin for us’ (2 Cor 5:21), i.e., made him suffer the punishment of sin, namely, when he was offered for our sins.”

Now, we would not go so far as to claim that Thomas’s whole soteriology is identical to Protestants; important differences remain one the matter of the application of Christ’s atonement to us. We, with Paul, teach that forgiveness of sins and righteousness is imputed to us through faith (Rom. 3:28, 4:5), and Thomas teaches that righteousness is infused in baptism.

But the matter of fact remains that, as to the accomplishment of the atonement, Thomas and Protestants agree that, in an act of penal substitution, Christ suffered, on the cross, in our place, bearing the punishment due to us for sin, in order to reconcile us to God. As Symington noted, the biblical doctrine of atonement is truly Catholic.

[1] William Symington, On the Atonement and Intercession of Jesus Christ (Edinburgh: William Whyte, 1834), p. 7