adherent vs backslider

adherent

noun
  • A person who has membership in some group, association or religion. 

adj
  • Adhesive, sticking to something. 

  • Having the quality of clinging or sticking fast to something. 

  • Attaching or pressing against a different organ. 

backslider

noun
  • A recidivist; one who backslides, especially in a religious sense; an apostate. 

  • She married him thinking to change his ways, and for a while he got religion, but he was ever a backslider; she soon began finding bottles stashed about the house. 

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