Numbers 25:7-8

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

⁸He went after the man of Israel into the pavilion, and thrust both of them through, the man of Israel, and the woman through her body. So the plague was stopped amongst the children of Israel.