Leviticus 22:4-6

MSB(i) 4 If a descendant of Aaron has a skin disease or a discharge, he may not eat the sacred offerings until he is clean. Whoever touches anything defiled by a corpse or by a man who has an emission of semen, 5 or whoever touches a crawling creature or a person that makes him unclean, whatever the uncleanness may be— 6 the man who touches any of these will remain unclean until evening. He must not eat from the sacred offerings unless he has bathed himself with water.