John Chrysostom

"But the righteousness which is of faith speaketh on this wise, Say not in thine heart, Who shall ascend into heaven (that is, to bring Christ down from above): or, Who shall descend into the deep? (that is, to bring up Christ again from the dead.) But what saith it? The word is nigh thee, even in thy mouth, and in thy heart, that is, the word of faith which we preach. …

Homily on Romans 17 ↗

Theophylact of Ohrid

Having learned that the works of the law cannot justify a person, learn how effortlessly and easily we are justified in Christ: for this requires faith from the heart and confession from the lips. But it is necessary to explain more fully what was said: "Who will ascend into heaven? Or who will descend into the abyss?" The Apostle borrowed this from Moses (Deut. 30:11–14), but in the sense that he understood according to his lofty wisdom. …

Commentary on Romans ↗

Irenaeus

For as it was not possible that the man who had once for all been conquered, and who had been destroyed through disobedience, could reform himself, and obtain the prize of victory; and as it was also impossible that he could attain to salvation who had fallen under the power of sin,-the Son effected both these things, being the Word of God, descending from the Father, becoming incarnate, stooping low, even to death, and consummating the arranged plan of our salvation, upon whom [Paul], exhorting us unhesitatingly to believe, again …

Against Heresies Book III ↗

Thomas Aquinas

Then when he says, but the justice which is of faith, he quotes Moses on justice based on faith. First, Moses shows the certitude of faith which ought to be in man's heart; second, the effect of faith, at but what says the Scripture? First, therefore, he says: Moses speaks not only of the justice based on the law, but also of that based on faith. But the justice which is of faith speaks thus, i.e., speaks in a man's heart, do not say in your heart, i.e., by doubting, who will ascend into heaven? …

Commentary on Romans ↗