cross the threshold of vs invade

cross the threshold of

invade

verb
  • To attack; to infringe; to encroach on; to violate. 

  • To move into. 

  • To enter by force in order to conquer. 

  • To infest or overrun. 

  • To make an unwelcome or uninvited visit or appearance, usually with an intent to cause trouble or some other unpleasant situation. 

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