aeviternity vs spiritual world

aeviternity

noun
  • Synonym of eternity (“existence without end”) 

  • Synonym of aevum (“the temporal mode of existence between time and eternity, said to be experienced by angels, saints, and celestial bodies (which medieval astronomy believed to be unchanging)”) 

spiritual world

noun
  • The afterlife. 

  • A metaphysical plane of existence parallel to the material world and occupied by spirits and other unearthly forces. 

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