penance

noun

• 1punishment inflicted on oneself as an outward expression of repentance for wrongdoing:he had done public penance for those hasty words

• 2a sacrament in which a member of the Church confesses sins to a priest and is given absolution. In the Roman Catholic Church often called sacrament of reconciliation.
• a religious observance or other duty required of a person by a priest as part of this sacrament to indicate repentance.

verb

• impose a penance on: the Bishop penanced him severely for his conduct