XXX.
(2) If a man vow a vow unto the Lord... — Two kinds of vows are spoken of in this verse — viz., the neder, which is here rendered vow, and which denotes primarily a positive vow, or vow of performance, and the issar, which is here rendered bond, and which denotes a negative vow, or a vow of abstinence. It is natural to suppose that at the expiration of the protracted wanderings in the wilderness the pious Israelites would be desirous of testifying their gratitude by dedicating themselves, or some portion of their substance beyond that which the law demanded, to the service of the Lord. And hence, although some regulations respecting vows had already been made (see Leviticus 27), it was needful that before their entrance into the land of Canaan some additions should be made to the law which pertained to the nature and obligation of vows.
He shall not break his word... — The sacred character of a vow is enforced in these words; and a timely caution was thus given to the Israelites that it was better for them not to vow than to vow and not to pay. (Comp. Ecclesiastes 5:2-5.)