Numbers 6:9

9. Defiled the head of his consecration Or, his consecrated head. Involuntary defilement by actual contact with a corpse was a violation of the Nazarite’s sanctity during seven days. “Cleanse thou me from secret” (unconsciously committed) “faults.” See Leviticus iv, concluding notes. If we may believe Hebrew writers, the subject of this vow could not even so much as wear mourning for his nearest relatives.

Shall shave his head Not because his hair is the special seat of the defilement, but because it was the conspicuous exponent of his entire consecration to Jehovah.