Catechism of the Catholic Church §983 — excerpt
Catechesis strives to awaken and nourish in the faithful faith in the incomparable greatness of the risen Christ's gift to his Church: the mission and the power to forgive sins through the ministry of the apostles and their successors:
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.
Also cites: St. Ambrose, De poenit. I, 15: PL 16, 490 · John Chrysostom, De sac. 3, 5: PG 48, 643 · St. Augustine, Sermo 213, 8: PL 38,1064