Leviticus 21:5-8

⁵They shall not make baldness on their heads, nor cut away the hair of their beards, nor scarify their flesh with marks.

⁶They shall be holy before their God, and shall not profane the Name of their God; for they offer the oblations of the Lord their God, and they shall be holy.

⁷They shall not take to wife a woman who is a harlot, or one who is corrupted, nor may they take a woman who hath been put away from her husband; for (the priest is to be) holy before his God.

⁸Thou shalt consecrate him, for he is to offer the oblation of thy God: he shall be sacred to thee; for I the Lord, who sanctify you, am Holy.