Numbers 6:5-7

New Revised Standard Version, Anglicised

⁵ All the days of their nazirite vow no razor shall come upon the head; until the time is completed for which they separate themselves to the Lord, they shall be holy; they shall let the locks of the head grow long.

⁶ All the days that they separate themselves to the Lord they shall not go near a corpse. ⁷ Even if their father or mother, brother or sister, should die, they may not defile themselves; because their consecration to God is upon the head.