Deuteronomy 13:12-15

12“If you hear [it said] in one of your cities, which the Lord your God gives you to live in,

13that some worthless and evil men have gone out from among you and have tempted the inhabitants of their city [to sin], saying, ‘Let us go and serve other gods’ (whom you have not known),

14then you shall investigate and search out [witnesses] and ask thorough questions. If it is true and the matter is established that this loathsome thing has been done among you,

15you shall most certainly strike the inhabitants of that city with the edge of the sword, utterly destroying it and all that is in it, even its livestock with the edge of the sword.