Leviticus 21:6, 8, 17, 21-22

They shall be holy unto their God, and not profane the name of their God: for the offerings of the LORD made by fire, and the bread of their God, they do offer: therefore they shall be holy.

Thou shalt sanctify him therefore; for he offereth the bread of thy God: he shall be holy unto thee: for I the LORD, which sanctify you, am holy.

Speak unto Aaron, saying, Whosoever he be of thy seed in their generations that hath any blemish, let him not approach to offer the bread of his God.

no man that hath a blemish of the seed of Aaron the priest shall come nigh to offer the offerings of the LORD made by fire: he hath a blemish; he shall not come nigh to offer the bread of his God. He shall eat the bread of his God, both of the most holy, and of the holy.