Numbers 25:6-9

Just then, while everyone was weeping in penitence at the entrance of the Tent of Meeting, an Israelite man, flaunting his behavior in front of Moses and the whole assembly, paraded a Midianite woman into his family tent. Phinehas son of Eleazar, the son of Aaron the priest, saw what he was doing, grabbed his spear, and followed them into the tent. With one thrust he drove the spear through the two of them, the man of Israel and the woman, right through their midsections. That stopped the plague from continuing among the People of Israel. But 24,000 had already died.