Leviticus 22:3-6

22:3 Say to them, ‘Throughout your generations, if any man from all your descendants approaches the holy offerings which the Israelites consecrate to the Lord while he is impure, that person must be cut off from before me. I am the Lord. 22:4 No man from the descendants of Aaron who is diseased or has a discharge may eat the holy offerings until he becomes clean. The one who touches anything made unclean by contact with a dead person, or a man who has a seminal emission, 22:5 or a man who touches a swarming thing by which he becomes unclean, or touches a person by which he becomes unclean, whatever that person’s impurity – 22:6 the person who touches any of these will be unclean until evening and must not eat from the holy offerings unless he has bathed his body in water.