Leviticus 21:1

Then Moses said to Aaron and to his sons Eleazar and Ithamar, “Do not uncover your heads nor tear your clothes, so that you will not die and that He will not become wrathful against all the congregation. But your relatives, the whole house of Israel, shall weep over the burning which Yahweh has brought about.

“Command the sons of Israel that they send away from the camp every leper and everyone having a discharge and everyone who is unclean because of a dead person.

‘All the days of his dedication as a Nazirite to Yahweh he shall not go near to a dead person.

‘The one who touches the corpse of any person shall be unclean for seven days.

“But they shall not go to a dead person to make themselves unclean; however, for father, for mother, for son, for daughter, for brother, or for a sister who has not had a husband, they may make themselves unclean.

The Holiness of the Priests