If a man vows a vow to the LORD, or swears an oath to bind himself by a pledge, he shall not break his word. He shall do according to all that proceeds out of his mouth.
2. If a man vow a vow. Wishing to modify the general law, lest any one should think that there was any contradiction in this exception, he begins by repeating the law itself, that every one should faithfully pay whatever he had vowed; as much as to say, that this stands good, but that he only refers to such as are their own masters; and...
This law was delivered to the heads of the tribes that they might instruct those who were under their charge, explain the law to them, give then necessary cautions, and call them to account, if there were occasion, for the breach of their vows.
Commenting on Numbers 30:1-2
If a man vow a vow unto the Lord,.... Which must be in a thing that is lawful to be done, which is not contrary to the revealed will and mind of God, and which may tend to the glory of God, the honour of religion, the service of the sanctuary, the good of a man's self or of his neighbour; or in things purely...