Numbers 6:5-7

King James Version

⁵ All the days of the vow of his separation there shall no razor come upon his head: until the days be fulfilled, in the which he separateth himself unto the Lord, he shall be holy, and shall let the locks of the hair of his head grow.

⁶ All the days that he separateth himself unto the Lord he shall come at no dead body.

⁷ He shall not make himself unclean for his father, or for his mother, for his brother, or for his sister, when they die: because the consecration of his God is upon his head.