Sefer HaChinuch ספר החינוך

That the nazirite not shave his hair: That the nazirite not shave his hair, all of the days of his naziriteness, as it is stated (Numbers 6:5), “a razor shall not pass over his head.”

I have written from the roots of the commandment below in the commandment of growing the hair of the nazirite (Sefer HaChinukh 374).

From the laws of the commandment — that which they, may their memory be blessed, said (Nazir 39a) that it is the same whether he shaves with a blade or with scissors like a blade or he plucked his hair with his hand, anytime that he cut it from the root, he is lashed, but anytime he left enough of it to bend its head to its root, he is not lashed, as this is not like a blade; [that] if he passed a salve over his head that removes hair and it removed his hair, he is not lashed, [but he did violate a positive commandment; (that) a nazirite who shaves all of his head is only lashed] for one shaving, but if they warned him about it for each and every hair, and he shaves [regardless], he is lashed for each and every one; so [too,] from the matter of the commandment, that which they said in Tractate Shabbat (50a), “A nazirite washes and separates, but he does not comb,” meaning to say he [may] wash his hair with his hand and separate it with his fingernails and if hairs fall from his washing and his separating, he [need] not be concerned, since it is not his intention to remove them, and it is also possible that they will not shed because of this, but he [may] not comb with a comb, since a comb will remove and shed hair without a doubt, and so [too,] he should not wash with dirt, as it will certainly remove hair, but if he does so, he is not lashed, and the rest of its details — are in Tractate Nazir.

And regarding who practices it, and at which time and the punishment of one who transgresses it, it is all like the law of the other commandments of the nazirite that we have written. And nonetheless, it should clarified here that if he shaves even one hair, he would be liable for lashes for it, and like they said in Nazir 40a, “Rav Chisda said, ‘To get lashes, [it is] with one hair; to invalidate, [it is] with two’” — meaning to say that he did not perform the commandment of shaving [at the end of his term] so long as two hairs remain on his head; “‘and to interrupt, he only interrupts with the majority of his head’” — meaning to say he only interrupts the tally of the days of his naziriteness if he shaves the majority of his head. But if he shaves its minority, he does not interrupt the tally of the days of his naziriteness with this, even though he has transgressed the negative commandment of “a razor shall not pass over his head.”

And this prohibition is practiced in all places and at all times by males and females, since anyone who accepts naziriteness upon himself — and even in our time — is prohibited from shaving even one hair. And one who transgresses this and shaved even one hair, is liable for lashes.