Augustine of Hippo, Against Two Letters of the Pelagians I.12: The Fourth Calumny,—That the Saints of the Old Testament are Said to Be Not Free from Sins

Chapter 12.—The Fourth Calumny,—That the Saints of the Old Testament are Said to Be Not Free from Sins.

“They say,” says he, “that the saints in the Old Testament were not without sins,—that is that they were not free from crimes even by amendment, but they were seized by death in their guilt.” Nay, I say that either before the law, or in the time of the Old Testament, they were freed from sins,—not by their own power, because “cursed is every one that hath put his hope in man,” and without any doubt those are under this curse whom also the sacred Psalm notifies, “who trust in their own strength;” nor by the old covenant which gendereth to bondage, although it was divinely given by the grace of a sure dispensation; nor by that law itself, holy and just and good as it was, where it is written, “Thou shalt not covet,” since it was not given as being able to give life, but it was added for the sake of transgression until the seed should come to whom the promise was made; but I say that they were freed by the blood of the Redeemer Himself, who is the one Mediator of God and man, the man Christ Jesus. But those enemies of the grace of God, which is given to small and great through Jesus Christ our Lord, say that the men of God of old were of a perfect righteousness, lest they should be supposed to have needed the incarnation, the passion, and resurrection of Christ, by belief in whom they were saved.