Numbers 6:5-9

5‘All the days of the vow of his separation no razor shall come upon his head; until the days are fulfilled for which he separated himself to the Lord, he shall be holy. Then he shall let the locks of the hair of his head grow.

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

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

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

9‘And if anyone 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.