Regulations concerning Priests

21 Then the Lord said to Moses, “Speak to the priests, the sons of Aaron, and say to them:

‘No one shall defile himself [that is, become ceremonially unclean] for the dead among his people [by touching a corpse or assisting in preparing it for burial], ² except for his relatives who are nearest to him, his mother, his father, his son, his daughter, and his brother, ³ also his virgin sister, who is near to him because she has had no husband; for her he may become unclean.