Deuteronomy 18:20
But the prophet who speaks a word presumptuously in my name, which I have not commanded him to speak, or who speaks in the name of other gods, that same prophet shall die.”
World English Bible (Public Domain)
In context
Before · Deuteronomy 18:18–19
18I will raise them up a prophet from among their brothers, like you. I will put my words in his mouth, and he shall speak to them all that I shall command him. 19It shall happen, that whoever will not listen to my words which he shall speak in my name, I will require it of him.
20But the prophet who speaks a word presumptuously in my name, which I have not commanded him to speak, or who speaks in the name of other gods, that same prophet shall die.”
After · Deuteronomy 18:21–22
21You may say in your heart, “How shall we know the word which the LORD has not spoken?” 22When a prophet speaks in the LORD’s name, if the thing doesn’t follow, nor happen, that is the thing which the LORD has not spoken. The prophet has spoken it presumptuously. You shall not be afraid of him.