Leviticus 21:6,8,17,21,22
They shall be holy to 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.
Nave's Topical Index—AKJV

Leviticus 22:25
Neither from a stranger's hand shall you offer the bread of your God of any of these; because their corruption is in them, and blemishes be in them: they shall not be accepted for you.
Nave's Topical Index—AKJV

1 Samuel 2:36
And it shall come to pass, that every one that is left in your house shall come and crouch to him for a piece of silver and a morsel of bread, and shall say, Put me, I pray you, into one of the priests' offices, that I may eat a piece of bread.
Nave's Topical Index—AKJV

2 Kings 23:9
Nevertheless the priests of the high places came not up to the altar of the LORD in Jerusalem, but they did eat of the unleavened bread among their brothers.
Nave's Topical Index—AKJV