In the sacramental rite of Reconciliation of a Penitent, penance is a task assigned by the priest to the person who has confessed his or her sins. It is something to be said or done as a sign of penitence and an act of thanksgiving for God's forgiveness (BCP, p. 446). The penitent may be assigned a psalm, prayer, or hymn to say, or an act of reparation to make. It may be assigned in light of the sins confessed and their context in the life of the penitent. It is assigned to the penitent before the priest or bishop pronounces absolution. Although a penance is not required in the rite of Reconciliation of a Penitent, it may be assigned as part of the "advice and counsel" given by the priest after the penitent's confession (BCP, p. 446). See Penitent; see Reconciliation of a Penitent.
Glossary definitions provided courtesy of Church Publishing Incorporated, New York, NY,(All Rights reserved) from "An Episcopal Dictionary of the Church, A User Friendly Reference for Episcopalians," Don S. Armentrout and Robert Boak Slocum, editors.