Leviticus 21:4-8

He shall not defile himself as a relative by marriage among his people, so as to profane himself.

They shall not shave any area on their heads bald, nor shave off the edges of their beards, nor make any cuts in their flesh.

They shall be holy to their God and not profane the name of their God, because they present the offerings by fire to the Lord, the food of their God; so they shall be holy.

They shall not take a woman who is a prostitute and profaned, nor shall they take a woman divorced from her husband; for he is holy to his God.

You shall consecrate him, therefore, because he offers the food of your God. He shall be holy to you; for I the Lord, who sanctifies you, am holy.