What does Leviticus 22:4 mean?

If a priest touches any crawling thing that makes him unclean, or touches a person who makes him unclean in any way, he can't eat the sacred food until evening. He has to wash himself with water first. Leviticus 22:4 - Modern Text Bible

(Contact with certain things or people makes a priest unclean for a time. He needs to wash and wait until evening before eating the offerings.)