Numbers 31:14-18

Moses was angry with the officers of the army, the captains of thousands and the captains of hundreds, who had come from service in the war. And Moses said to them, “Have you spared all the women? Behold, these caused the sons of Israel, through the counsel of Balaam, to trespass against the LORD in the matter of Peor, so the plague was among the congregation of the LORD. Now therefore, kill every male among the little ones, and kill every woman who has known man intimately. But all the girls who have not known man intimately, spare for yourselves.