commandment vs firman

commandment

noun
  • A divinely ordained command, especially one of the Ten Commandments. 

  • The offence of commanding or inducing another to violate the law. 

firman

noun
  • A royal decree issued by a sovereign in certain historical Islamic states, especially by the Sultan of Turkey. 

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