Deuteronomy 18:20-22

Douay-Rheims 1899 American Edition

²⁰ But the prophet, who being corrupted with pride, shall speak in my name things that I did not command him to say, or in the name of strange gods, shall be slain.

²¹ And if in silent thought thou answer: How shall I know the word that the Lord hath not spoken?

²² Thou shalt have this sign: Whatsoever that same prophet foretelleth in the name of the Lord, and it cometh not to pass: that thing the Lord hath not spoken, but the prophet hath forged it by the pride of his mind: and therefore thou shalt not fear him.