didactic vs sermonizing

didactic

adj
  • Instructive or intended to teach or demonstrate, especially with regard to morality. 

  • Excessively moralizing. 

  • Teaching from textbooks rather than laboratory demonstration and clinical application. 

sermonizing

noun
  • The giving of sermons. 

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