Spiritual vs miserere

Spiritual

noun
  • A member of a branch of the Franciscan order that advocated simple dress and renounced the owning of property. 

miserere

noun
  • A small projecting boss or bracket on the underside of the hinged seat of a church stall, intended to give some support to a standing worshipper when the seat is turned up; a misericord. 

  • An expression of lamentation or complaint. 

  • Ileus. 

  • A medieval dagger, used for the mercy stroke to a wounded foe; misericord. 

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