Afflict the soul, i.e. herself by fasting, which oft goes under that name, as Leviticus 16:29,31 Leviticus 23:27,32 Isa 58:5, by watching, or the like. And these words are added not for limitation, for it is manifest from Numbers 30:5,8,10,12, that the power of parents and husbands was more general and large; but for amplification, to show that the husband had this power not only in those vows which concerned himself or his estate, but also in those which might seem only to concern her own person or body. And the reason hereof is, because the wife's person or body being the husband's right, she might not do any thing to the injury of her body without his consent.
Related Commentaries of Numbers 30:13
Numbers 30:13
13 Every vow, and every binding oath to afflict the soul, her husband may establish it, or her husband may make it void.