Deuteronomy 18:19-21

New Century Version

¹⁹ This prophet will speak for me; anyone who does not listen when he speaks will answer to me. ²⁰ But if a prophet says something I did not tell him to say as though he were speaking for me, or if a prophet speaks in the name of other gods, that prophet must be killed.”

²¹ You might be thinking, “How can we know if a message is not from the Lord?”