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.

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.

But the prophet who takes it on himself to say words in my name which I have not given him orders to say, or who says anything in the name of other gods, will come to his death.

But if a prophet, having been corrupted by arrogance, chooses to speak, in my name, things which I did not instruct him to say, or to speak in the name of foreign gods, he shall be put to death.

Compare the marginal references.

But the prophet which shall presume to speak in my name,.... Pretending a mission and commission from God, and yet was never sent by him, like the prophets in Jeremiah 23:21,
which I have not commanded him to speak; which though true was not to be spoken in a public manner, by assuming a public office, without a divine authority or a commission from God, and much less what was false, and never commanded to be spoken at all by any:
or, that shall speak in the name of other gods; the idols of the people, as the Targum; as if any should affirm they were sent by Jove, or inspired by Apollo, as some are said to prophesy by Baal, as if they had received their orders and instructions from him, and were inspired by him, Jeremiah 2:8.
even that prophet shall die; the Targum of Jonathan is, be killed by the sword, but the Jews (q) generally interpret it of strangling.
(q) Misn. Sanhedrin, c. 10. sect. 1. Bartenora in ib sect. 5. and Jarchi in loc.