apostate vs double agent

apostate

adj
  • Guilty of apostasy. 

noun
  • A person who has renounced a religion or faith. 

  • One who, after having received sacred orders, renounces his clerical profession. 

double agent

noun
  • A spy who pretends to work for one side, when they are actually working for or passing information to the other. 

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