Sacrament of Reconciliation

The Sacrament of Reconciliation has also been known as the Sacrament of Penance, and as Confession.

Those who approach the Sacrament of Penance obtain pardon from God's mercy for the offense committed against him, and are, at the same time, reconciled with the Church which they have wounded by their sins and which by charity, by example, and by prayer labors for their conversion.
Catechism of the Catholic Church 1422