Daily, the just man sings: I was assailed so as to fall but I did not fall because the Lord upheld me. But even when he falls he will not be cast headlong, for the Lord is the support of his hand; that is, when he sins he will not be condemned because he has Jesus as his advocate. Although he falls seven times a day, seven times he rises again. He does not take pleasure in lying where he falls and wallowing in the mire, but rising speedily he shakes off the dust and washes away the dirt by making satisfaction. It is through this that he becomes just; when he opens his mouth, he is always the accuser of himself, mindful of God’s advice which bids him, Tell your iniquities in order to be justified. So it comes about that while he judges himself and gives God satisfaction of himself, even in his guilt he obtains an advocate whom he feared as his just judge.
For the Lord is just and loves justice; he, who will judge in justice in due time, cannot uphold or protect unjust causes. And yet he, who threatens to come as judge of those who proudly presume on their justice, promises to be the advocate of those who humbly confess their sins. With him, in whose sight no one shall be justified, we cannot in any way justify our cause better than by accusing and punishing ourselves and thus transfer his justice to ourselves and play the part of the just against the guilty.
Guerric of Igny, Liturgical Sermons, Book 1, Sermon 20: the First Sermon for Lent