16 But of her children there are some who nevertheless forget the greatness of their calling and election. They mar their God-given beauty, and fail to mirror in themselves the image of Jesus Christ. We cannot find it in Us to threaten or abuse them, for the love We bear them is a father's love. Instead We appeal to them in the words of the Council of Trent—the best restorative for Catholic discipline. "When we put on Christ in baptism ( Gal. 3.27), we become in Him an entirely new creature and obtain the full and complete remission of every sin. It is only with great effort and with great compunction on our part that we can obtain the same newness and sinlessness in the sacrament of penance, for such is the stipulation of divine justice. That is why the holy Fathers called penance 'a laborious kind of baptism'."(16)
Source: Paenitentiam Agere (Vatican.va)