Thematic Bible: Specially required to avoid

And Jehovah said to Moses, Speak to the priests, the sons of Aaron, and say to them, There shall none be defiled for the dead among his people. But for his kin that is near him, for his mother and for his father and for his son and for his daughter and for his brother and for his sister, a virgin, who is near to him, who has had no husband, for her he may be defiled. read more.
A leader shall not defile himself among his people, to pollute himself. They shall not make baldness on their head, nor shall they shave the corner of their beard, nor make any cutting in their flesh. They shall be holy to their God and not profane the name of their God. For they offer the fire offerings of Jehovah, the bread of their God. Therefore they shall be holy.

Neither shall he come near to any dead person, nor defile himself for his father nor for his mother. Neither shall he go out of the sanctuary, nor profane the sanctuary of his God; for the crown of the anointing oil of his God is on him. I am Jehovah.