Numbers 25:7-9

When Phinehas the son of Eleazar, the son of Aaron the priest, saw it, he arose from the midst of the congregation and took a spear in his hand, and he went after the man of Israel into the tent and pierced both of them through, the man of Israel and the woman, through the body. So the plague on the sons of Israel was checked. Those who died by the plague were 24,000.