constancy vs obedience

constancy

noun
  • The quality of being constant; steadiness or faithfulness in action, affections, purpose, etc. 

  • An unchanging quality or characteristic of a person or thing. 

obedience

noun
  • The quality of being obedient. 

  • The collective body of persons subject to any particular authority. 

  • A written instruction from the superior of an order to those under him. 

  • Any official position under an abbot's jurisdiction. 

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