Leviticus 22:3-6

Say to them, ‘Any one of your descendants throughout your generations who approaches the holy things which the Israelites dedicate to the LORD, while he is [ceremonially] unclean, that person shall be cut off from My presence and excluded from the sanctuary; I am the LORD. No man of the descendants of Aaron who is a leper or has a discharge may eat the holy things [the offerings and the showbread] until he is clean. And whoever touches any person or thing made unclean by contact with a corpse or a man who has had a seminal emission, or whoever touches any crawling thing by which he is made unclean, or any person by whom he is made unclean, whatever it may be, [Lev 11:24-28] the person who touches any such thing shall be unclean until evening and shall not eat the holy things unless he has bathed his body in water. [Heb 10:22]