Leviticus 21:6-7

6They 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.

7“Priests may not marry a woman defiled by prostitution, and they may not marry a woman who is divorced from her husband, for the priests are set apart as holy to their God.