absolve vs expiate

absolve

verb
  • To pronounce free from or give absolution for a penalty, blame, or guilt. 

  • To pronounce not guilty; to grant a pardon for. 

  • To grant a remission of sin; to give absolution to. 

  • To remit a sin; to give absolution for a sin. 

  • To pass a course or test; to gain credit for a class; to qualify academically. 

  • To set free, release or discharge (from obligations, debts, responsibility etc.). 

expiate

verb
  • To make amends or pay the penalty for. 

  • To wind up, bring to an end. 

  • To purify with sacred rites. 

  • To atone or make reparation for. 

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