Roman Catechism 19.79

Chapter 19 — Part II: The Sacraments — Penance

Section 79. Nay more, the same Prophet declares elsewhere that, as soon as we have conceived this contrition in our hearts, our sins are forgiven by God: I said, I will confess my injustice to the Lord, and thou hast forgiven the wickedness of my sin. Of this truth we have a figure in the ten lepers, who, when sent by our Lord to the priests, were cured of their leprosy before they had reached them; which gives us to understand that such is the efficacy of true contrition, of which we have spoken above, that through it we obtain from the Lord the immediate pardon of all sins.