From The Art and Popular Culture Encyclopedia
Penance is repentance of sins as well as the proper name of the Catholic and Orthodox Christian Sacrament of Penance and Reconciliation/Confession. The word penance derives from Old French and Latin poenitentia, both of which derive from the same root meaning repentance, the desire to be forgiven; (in English see (contrition)). Penance and repentance, similar in their derivation and original sense, have come to symbolize conflicting views of the essence of repentance, arising from the controversy as to the respective merits of "faith" and "good works." Word derivations occur in many languages.