Numbers 25:3-8

³And Israel joined himself unto the Baal of Peor; and the anger of the LORD was kindled against Israel.

⁴And the LORD said unto Moses: 'Take all the chiefs of the people, and hang them up unto the LORD in face of the sun, that the fierce anger of the LORD may turn away from Israel.'

⁵And Moses said unto the judges of Israel: 'Slay ye every one his men that have joined themselves unto the Baal of Peor.'

⁶And, behold, one of the children of Israel came and brought unto his brethren a Midianitish woman in the sight of Moses, and in the sight of all the congregation of the children of Israel, while they were weeping at the door of the tent of meeting.

⁷And when Phinehas, the son of Eleazar, the son of Aaron the priest, saw it, he rose up from the midst of the congregation, and took a spear in his hand.

⁸And he went after the man of Israel into the chamber, and thrust both of them through, the man of Israel, and the woman through her belly. So the plague was stayed from the children of Israel.