Penance
Penance is repentance of sins, as well as the name of the Catholic Sacrament of Penance and Reconciliation/Confession.  The word penance comes from the Latin poenitentia, the same root as penitence, which in English means repentance, the desire to be forgiven, or contrition: in many languages there is only one single word for it.  Penance and repentance were similar in their original sense. After the controversy about the merits of "faith" and "good works" they are seen as conflicting views.