unfaithfulness vs zeal

unfaithfulness

noun
  • The characteristic of being unfaithful; infidelity; disloyalty. 

zeal

noun
  • The fervour or tireless devotion for a person, cause, or ideal and determination in its furtherance; diligent enthusiasm; powerful interest. 

  • The collective noun for a group of zebras. 

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