Deuteronomy 13:6; Deuteronomy 13:9

6 If your very own brother, or your son or daughter, or the wife you love, or your closest friend secretly entices you, saying, “Let us go and worship other gods” (gods that neither you nor your ancestors have known,

9 You must certainly put them to death. Your hand must be the first in putting them to death, and then the hands of all the people.