loyalty vs piety

loyalty

noun
  • Faithfulness or devotion to some person, cause or nation. 

  • The state of being loyal; fidelity. 

piety

noun
  • Reverence and devotion to God. 

  • A devout act or thought. 

  • A belief that is accepted unthinkingly and with undue reverence. 

  • Similar reverence to one's parents and family or to one's country. 

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