Deuteronomy 13:5

And that prophet, or that dreamer of dreams, shall be put to
death
Which death, according to the Targum of Jonathan, was to be killed with the sword:

because he hath spoken to turn you away from the Lord your God;
or "spoken revolt against the Lord" ^F12, high treason against him, delivering out doctrine that tends to cause his subjects to rebel against him, and revolt from him; and therefore he is justly deserving of death, to draw off a people from him he had been so good and kind unto; so that to apostasy would be added the sin of ingratitude:

which brought you out of the land of Egypt, and redeemed you out of the
house of bondage;
and so was not only their Lord by creation whom they ought to serve, but by redemption, which laid them under double obligation to serve him:

to thrust thee out of the way which the Lord thy God commanded thee to
walk in;
not by external force, but by the power of persuasion, by enticing words and arguments:

so shalt thou put the evil away from the midst of thee;
the evil man, by putting him to death, and the evil of idolatry, by not listening to the words of the false prophet.