Numbers 6:7
Even if their own father, mother, brother, or sister dies, they must not make themselves unclean by going near them. Nazarites show their vow to God with their long hair.
Numbers 9:6
There were some men who had become unclean from touching a dead body. They could not celebrate the Passover that day. They went to Moses and Aaron.
Leviticus 21:1-2
Jehovah gave Moses these instructions for Aaron's sons, the priests: Touching a dead body will make you unclean. So do not go near a dead relative,
Leviticus 21:10-12
The priest who is anointed with oil and wears the chief priest's clothes is chief over his brothers. He must never mourn by leaving his hair uncombed or by tearing his clothes.
Ezekiel 44:25
A priest must not make himself unclean by going near a dead body. But a priest may become unclean if the dead person is his father, mother, son, daughter, brother, or unmarried sister.