Numbers 25:3-5

³And Israel consecrated themselves to Baal-peor; and the Lord was very angry with Israel.

⁴And the Lord said to Moses, Take all the princes of the people, and make them examples of judgment for the Lord in the face of the sun, and the anger of the Lord shall be turned away from Israel.

⁵And Moses said to the tribes of Israel, Slay ye every one his friend that is consecrated to Baal-peor.