Deuteronomy 17:3-5

That person may have served other gods and bowed down to them or to the sun or moon or stars of the sky, which I have commanded should not be done. If someone has told you about it, you must look into the matter carefully. If it is true that such a hateful thing has happened in Israel, take the man or woman who has done the evil thing to the city gates and throw stones at that person until he dies.