"inflict trouble or pain on for the purpose of correction," 1520s, with -en (1) + the word it replaced, obsolete verb chaste "to correct (someone's) behavior" (Middle English chastien, c. 1200), from Old French chastiier "to punish" (see chastise). Now chiefly in reference to moral discipline, divine rather than corporal punishment. Related: Chastened; chastening.
Whom the Lord loveth he chasteneth [Hebrews xii.6]