aeviternity vs deathlessness

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)”) 

deathlessness

noun
  • The state of being deathless; eternity; immortality. 

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