forgive (v.) Look up forgive at
Old English forgiefan "give, grant, allow; remit (a debt), pardon (an offense)," also "give up" and "give in marriage" (past tense forgeaf, past participle forgifen); from for-, here probably "completely," + giefan "give" (see give (v.)).

The sense of "to give up desire or power to punish" (late Old English) is from use of such a compound as a Germanic loan-translation of Vulgar Latin *perdonare (Old Saxon fargeban, Dutch vergeven, German vergeben "to forgive," Gothic fragiban "to grant;" and see pardon (n.)). Related: Forgave; forgiven; forgiving.