mulct vs penance

mulct

verb
  • To impose such a fine or penalty. 

  • To swindle (someone) out of money. 

noun
  • A fine or penalty, especially a pecuniary one. 

penance

verb
  • To impose penance; to punish. 

noun
  • Any instrument of self-punishment. 

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

  • A sacrament in some Christian churches. 

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