indifference vs penance

indifference

noun
  • Unconcerned nonchalance. 

  • The state of being indifferent. 

  • Unbiased impartiality. 

  • Unemotional apathy. 

  • Self-identity defined through the negation of difference, non-difference. 

  • A lack of enthusiasm. 

penance

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. 

verb
  • To impose penance; to punish. 

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