expiate vs propitiate

expiate

verb
  • To atone or make reparation for. 

  • To wind up, bring to an end. 

  • To make amends or pay the penalty for. 

  • To purify with sacred rites. 

propitiate

verb
  • To make propitiation. 

  • To make propitious or favourable. 

  • To conciliate, appease, or make peace with someone, particularly a god or spirit. 

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