Psalms 51:9

God does not listen to sinners. When he was beating his breast, he was punishing his sins; when he was punishing his sins, he was associating himself with God as judge. God, you see, hates sins; if you too hate them, you are beginning to join God, so that you can say to him, "Turn your face away from my sins." Turn your face away—but from what? From my sins. "Do not turn your face away from me." What's the meaning of "your face from my sins"? Don't see them, don't look at them; overlook them instead, so that you can pardon me.

So all past sins are forgiven people on conversion; but for the rest of this life there are certain grave and deadly sins, from which one can be released only by the most vehement and distressing humbling of the heart and contrition of spirit and the pain of repentance. These are forgiven through the keys of the church. If you start judging yourself, you see, if you start being displeased with yourself, God will come along to show you mercy. If you are willing to punish yourself, he will spare you. In fact, all who repent and do penance well are punishing themselves. They have to be severe with themselves, so that God may be lenient with them. As David says, "Turn your face away from my sins, and blot out all my iniquities." But on what terms? He says in the same psalm, "Since I acknowledge my iniquity, and my sin is always before me." So if you acknowledge it, God overlooks it.

"Turn Thou away Your face from my sins, and all mine iniquities blot out" [Psalm 51:9]. For now bones humbled exult, now with hyssop cleansed, humble I have become. "Turn Thou away Your face," not from me, but "from my sins." For in another place praying he says, "Turn not away Your face from me." He that would not that God's face be turned away from himself, would that God's face be turned away from his sins. For to sin, when God turns not Himself away, he adverts: if he adverts, he animadverts. "And all mine iniquities blot out." He is busied with that capital sin: he reckons on more, he would have all his iniquities to be blotted out: he relies on the Physician's hand, on that "great mercy," upon which he has called in the beginning of the Psalm: "All mine iniquities blot out." God turns away His face, and so blots out; by "turning away" His face, sins He blots out. By "turning towards," He writes them. You have heard of Him blotting out by turning away, hear of Him by turning towards, doing what? "But the countenance of the Lord is upon men doing evil things, that He may destroy from the earth the remembrance of them:" He shall destroy the remembrance of them, not by "blotting out their sins." But here he does ask what? "Turn away Your face from my sins." Well he asks. For he himself does not turn away his face from his own sins, saying, "For my sin I acknowledge." With reason you ask and well ask, that God turn away from your sin, if you from thence dost not turn away your face: but if you set your sin at your back, God does there set His face. Do thou turn sin before your face, if you will that God thence turn away His face; and then safely you ask, and He hears.