penance vs reward

penance

noun
  • A voluntary self-imposed punishment for a sinful act or wrongdoing. It may be intended to serve as reparation for the act. 

  • Any instrument of self-punishment. 

  • A sacrament in some Christian churches. 

verb
  • To impose penance; to punish. 

reward

noun
  • Something of value given in return for an act. 

  • A prize promised for a certain deed or catch 

  • The result of an action, whether good or bad. 

verb
  • To give a reward to or for. 

  • To recompense. 

How often have the words penance and reward occurred in a corpus of books? (source: Google Ngram Viewer )