Exodus 32:27

32:27 and he said to them, “Thus says the Lord, the God of Israel, ‘Each man fasten his sword on his side, and go back and forth from entrance to entrance throughout the camp, and each one kill his brother, his friend, and his neighbor.’”

Deuteronomy 13:6-11

False Prophets in the Family

13:6 Suppose your own full brother, your son, your daughter, your beloved wife, or your closest friend should seduce you secretly and encourage you to go and serve other gods that neither you nor your ancestors have previously known, 13:7 the gods of the surrounding people (whether near you or far from you, from one end of the earth to the other). 13:8 You must not give in to him or even listen to him; do not feel sympathy for him or spare him or cover up for him. 13:9 Instead, you must kill him without fail! Your own hand must be the first to strike him, and then the hands of the whole community. 13:10 You must stone him to death because he tried to entice you away from the Lord your God, who delivered you from the land of Egypt, that place of slavery. 13:11 Thus all Israel will hear and be afraid; no longer will they continue to do evil like this among you.

Ezekiel 9:5-7

9:5 While I listened, he said to the others, “Go through the city after him and strike people down; do no let your eye pity nor spare anyone! 9:6 Old men, young men, young women, little children, and women – wipe them out! But do not touch anyone who has the mark. Begin at my sanctuary!” So they began with the elders who were at the front of the temple.

9:7 He said to them, “Defile the temple and fill the courtyards with corpses. Go!” So they went out and struck people down throughout the city.