eternize vs maintain

eternize

verb
  • To make or render eternal. 

  • To prolong indefinitely. 

  • To immortalize; to make eternally famous. 

maintain

verb
  • To keep up; to preserve; to uphold (a state, condition etc.). 

  • To declare or affirm (a clause) to be true; to assert. 

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