Leviticus 22:4-5

4If a son of Aaron has a skin disease, he must not eat the holy gifts. If pus is coming from his body, he is not clean. He must not eat the holy offerings until he is clean. He might touch something that has touched a dead body. Or if he touches an unclean man, he will become unclean. The man may be unclean because semen is coming from his body.

5Aaron's son might touch an animal that moves on its stomach. Or he might touch a person who is not clean. If he does, Aaron's son will be unclean.