Leviticus 21:6

6 They must be holy to their God and must not profane the name of their God. Because they present the food offerings to the LORD, the food of their God, they are to be holy.

Read Leviticus 21:6 Using Other Translations

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.
They shall be holy to their God and not profane the name of their God. For they offer the LORD's food offerings, the bread of their God; therefore they shall be holy.
They must be set apart as holy to their God and must never bring shame on the name of God. They must be holy, for they are the ones who present the special gifts to the LORD, gifts of food for their God.