Numbers 6:5-9

5"All the days of his vow of separation, no razor shall touch his head. Until the time is completed for which he separates himself to the Lord, he shall be holy. He shall let the locks of hair of his head grow long.

6"All the days that he separates himself to the Lord he shall not go near a dead body.

7Not even for his father or for his mother, for brother or sister, if they die, shall he make himself unclean, because his separation to God is on his head.

8All the days of his separation he is holy to the Lord.

9"And if any man dies very suddenly beside him and he defiles his consecrated head, then he shall shave his head on the day of his cleansing; on the seventh day he shall shave it.