Verse 1
Numbers 30:1. Moses spake unto the heads of the tribes — The chief rulers of each tribe, who were to communicate it to the rest. This is the thing the Lord hath commanded — With relation to vows, concerning which, it is probable, some case had been proposed to him to be determined.

Verse 2
Numbers 30:2. If a man vow a vow — Concerning something lawful, and in his power to perform. Unto the Lord — To the honour and service of God. Or swear an oath — Confirm his vow by an oath. To bind his soul with a bond — To restrain himself from something otherwise lawful; as, suppose, from such a sort of meat or drink; or to oblige himself to the performance of something otherwise not necessary, as to observe a private day of fasting. He shall not break (Hebrew, he shall not profane) his word — Not render his word, and consequently himself, profane, or contemptible in the eyes of others. He shall do according to all that proceedeth out of his mouth — Punctually and conscientiously. His vow shall be performed in the manner, time, and kind which was at first proposed, in reverence to the great God to whom it was made. But in case a man vows, or takes an oath, to do any thing that is in itself unlawful, as those Jews did, mentioned Acts 23:14, nothing can be plainer than that such vow or oath must be void in the very nature of the thing. For promises and resolutions, enforced by the strongest oaths, or most solemn vows, are but secondary obligations, and therefore can never absolve us from our primary and immutable obligation to obey the laws of God and nature; for this would be to say, that we could, by an oath, oblige ourselves to do what God had before obliged us not to do. “He who perpetrates any act of injustice,” says Philo Judæus, de specialibus legibus, “upon account of his oath, adds one crime to another; first by taking an unlawful oath, and then by doing an unlawful action. Therefore such a one ought to abstain from the unjust action, and pray God to pardon him for his rash oath.” Thus Herod ought to have done; instead of performing the rash promise which he had sealed with an oath, he ought to have punished that wicked woman, who instigated him to commit murder, under pretence of fulfilling his oath, Matthew 14:9. Grotius observes further, that though the thing promised be not absolutely unlawful, yet, if it obstruct some greater moral good, such a promise, even sealed with an oath, is not binding.

Verse 4
Numbers 30:4. And her father hear her vow — Either when she spake the words, or by her acquainting him therewith, as she was bound to do. If it be asked why sons are not mentioned as well as daughters, since both, in their younger years, are under the power of their parents; the answer is, that the cases are quite different; for the sons may soon have it in their power, when become masters of families, to perform the vows which they had made in their minority; but daughters, who pass from the father’s jurisdiction into the power of a husband, are perpetually dependant, either upon their fathers or husbands, and so have no right to make vows without the consent either of the one or the other, except in the case of widowhood or divorce, which is specified, Numbers 30:9.

Verse 5
Numbers 30:5. In the day that he heareth — Speedily, or without delay, allowing only convenient time for deliberation. And it is hereby intimated, that the day or time he had for disallowing her vow was not to be reckoned from her vowing, but from his knowledge of her vow. The Lord shall forgive — Or, will forgive her not performing it. But this should be understood only of vows which could not be performed without invading the father’s right; for if one should vow to forbear such or such a sin, and all occasions or means leading to it, and to perform such or such duties, when he had opportunity, no father can discharge him from such vows. If this law does not extend to children’s marrying without the parent’s consent, so far as to put it in the power of the parent to disannul the marriage, (which some think it does,) yet certainly it proves the sinfulness of such marriages, and obliges those children to repent and humble themselves before God and their parents.

Verse 9
Numbers 30:9. Widow or divorced — Though she be in her father’s house, whither such persons often returned.

Verse 10
Numbers 30:10. If she vowed — If she that now is a widow, or divorced, made that vow while her husband lived with her; as, suppose, she then vowed that if she was a widow she would give such a proportion of her estate to pious or charitable uses, of which vow she might repent when she came to be a widow, and might believe or pretend she was free from it, because that vow was made in her husband’s lifetime: this is granted, in case her husband then disallowed it; but denied, in case, by silence, or otherwise, he consented to it.

Verse 13
Numbers 30:13. To afflict the soul — Herself, by fasting, by watching, or the like. And these words are added 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 and body; and the reason 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.

Verse 15
Numbers 30:15. After he hath heard — And approved them by his silence from day to day; if after that time he shall hinder them, which he ought not to do, her non-performance of her vow shall be imputed to him, not to her.