Numbers 31:17 in the King James Version
Now therefore kill every male among the little ones, and kill every woman that hath known man by lying with him.
Context
16 Behold, these caused the children of Israel, through the counsel of Balaam, to commit trespass against the LORD in the matter of Peor, and so the plague was among the congregation of the LORD.
17 Now therefore kill every male among the little ones, and kill every woman who has known man by lying with him.
18 But all the girls, who have not known man by lying with him, keep alive for yourselves.