in the book Insight on the Scriptures 1988 Watchtower bible and tract society on page 696 under the heading prophet and subheading distinguishing the true form the false.
page 696 it says
The three essentials for establishing the credentials of a true prophet, as given through Moses were. The true prophet would speak in Jehovah's name; the things foretold would come to pass (De 18:20-22): and his prophesying must promote true worship,being in harmony with God's revealed word and commandments (De 13;1-4)