Leviticus 21:18-21

18 No man may serve me if he has anything wrong with his body. He must not be blind. He must not have a weak leg or one leg that is shorter than the other leg. He must not have any part of his face that is the wrong shape. 19 He must not have an arm or a leg that is broken. 20 He must not have a back that is not straight. He must not be very small and thin. He must not have an eye disease or a skin disease. He must not have testicles that are spoiled.

21:20Testicles are the sex parts of a man that give him the power to create children.

21 No descendant of Aaron who has something wrong with his body may serve me as a priest. He may not offer gifts to me, the Lord. His body is not perfect, so he may not bring offerings of food to his God.