Deuteronomy 17:3-5

3and has gone and 1served other gods and worshiped them, 2or the sun or the moon or any of the heavenly host, 3which I have not commanded,

4and if it is told you and you have heard of it, then you shall inquire thoroughly. Behold, if it is true and the thing certain that this detestable thing has been done in Israel,

5then you shall bring out that man or that woman who has done this evil deed to your gates, that is, the man or the woman, and 4you shall stone them to 5death.