arouse vs light a fire under

arouse

verb
  • To stimulate or induce (feelings). 

  • To sexually stimulate. 

  • To cause an erection of the penis or other physical signs of sexual arousal, such as fluid secretion. 

  • To wake from sleep or stupor; to rouse. 

light a fire under

verb
  • To motivate or encourage (someone) to start sooner or move faster. 

How often have the words arouse and light a fire under occurred in a corpus of books? (source: Google Ngram Viewer )