agony vs purgatory

agony

noun
  • The last struggle of life; death struggle. 

  • Extreme pain. 

  • Violent contest or striving. 

  • Paroxysm of joy; keen emotion. 

  • The sufferings of Jesus Christ in the garden of Gethsemane. 

purgatory

noun
  • Any situation where suffering is endured, particularly as part of a process of redemption. 

adj
  • Tending to cleanse; expiatory. 

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