Deuteronomy 18:18-20

YLT(i) 18 a prophet I raise up to them, out of the midst of their brethren, like to thee; and I have given my words in his mouth, and he hath spoken unto them all that which I command him; 19 and it hath been—the man who doth not hearken unto My words which he doth speak in My name, I require it of him. 20 `Only, the prophet who presumeth to speak a word in My name—that which I have not commanded him to speak—and who speaketh in the name of other gods—even that prophet hath died.