Leviticus 21:4-6

New Century Version

⁴ But a priest must not make himself unclean if the dead person was only related to him by marriage.

⁵ “‘Priests must not shave their heads, or shave off the edges of their beards, or cut their bodies. ⁶ They must be holy to their God and show respect for God’s name, because they present the offerings made by fire to the Lord, which is the food of their God. So they must be holy.