Augustine of Hippo

For how did He turn away the captivity of Jacob? See, how that that setting free is spiritual, see how that it is done inwardly. "You have forgiven," he says, "the iniquity of Your people: You have covered all their sins" [Psalm 85:2]. Behold how He has turned away their captivity, in that He has remitted iniquity: iniquity held them captive; your iniquity forgiven, you are freed. Confess therefore that you are in captivity, that you may be worthy to be freed: for he that knows not of his enemy, how can he invoke the liberator? …

Exposition on Psalm 85 ↗

Jerome

You have forgiven the iniquity of your people. This we believe was accomplished in baptism. You have covered all their sins. This in penance, as is said in the thirty-first psalm: "Blessed are they whose iniquities are forgiven, and whose sins are covered." In baptism our iniquities are forgiven us, but in penance the sins that had been committed are covered over: they are not dismissed, but covered over. Let us carefully consider the force of the word. …

Homily 64, on Psalm 84 (Alternate Series) ↗