Leviticus 21:5 (KJV)

And the LORD said unto Moses, Speak unto the priests the sons of Aaron, and say unto them, There shall none be defiled for the dead among his people:

But for his kin, that is near unto him, that is, for his mother, and for his father, and for his son, and for his daughter, and for his brother.

And for his sister a virgin, that is nigh unto him, which hath had no husband; for her may he be defiled.

But he shall not defile himself, being a chief man among his people, to profane himself.

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 not take a wife that is a whore, or profane; neither shall they take a woman put away from her husband: for he is holy unto his God.

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.

And the daughter of any priest, if she profane herself by playing the whore, she profaneth her father: she shall be burnt with fire.

And he that is the high priest among his brethren, upon whose head the anointing oil was poured, and that is consecrated to put on the garments, shall not uncover his head, nor rend his clothes;