Thematic Bible: Specially required to avoid

And the Lord said to Moses, Say to the priests, the sons of Aaron, Let no man make himself unclean for the dead among his people; But only for his near relations, for his mother or his father, his son or his daughter, and his brother; And for his sister, a virgin, for she is his near relation and has had no husband, he may make himself unclean. read more.
But let him, being a chief among his people, not make himself unclean in such a way as to put shame on himself. They are not to have their hair cut off for the dead, or the hair on their chins cut short, or make cuts in their flesh. Let them be holy to their God and not make the name of their God common; for the fire offerings of the Lord and the bread of their God are offered by them, and they are to be holy.

He may not go near any dead body or make himself unclean for his father or his mother; He may not go out of the holy place or make the holy place of his God common; for the crown of the holy oil of his God is on him: I am the Lord.