We have sworn by the Lord - Judges 21:7
Amid the gross evils of this time, the people of Israel were very tenacious of their vows, which had been ratified in the presence of God, and under the solemn sanctions of the Tabernacle. Because they had sworn not to give their daughters in marriage to Benjamin, they had to devise an expedient to obtain wives for the six hundred who had escaped massacre, that the tribe should not become extinct.
The same spirit was manifested by Jephthah, when he said, "I have opened my mouth to the Lord; I cannot go back." No doubt there was the implied conviction that God would avenge the violation of an oath solemnly taken in His name.
What new emphasis is added by this conception to the words of the Epistle to the Hebrews: "God, willing to show unto the heirs of promise the immutability of His counsel, confirmed it by an oath." Since He could swear by no greater, He swore by Himself, that He would bless and multiply Abraham and his seed. If then you are of the faith of faithful Abraham, you have the right to claim the fulfillment of God's promise in this double aspect: He will bless and multiply. And it is impossible for Him to alter or fail in the word He hath spoken.
The Psalmist said that God's statutes; i. e., the things which He established, were His songs. Surely we have every reason to sing, who know that the covenant of God's love is as steadfast as His throne. Let us turn His statutes into songs. He has given us exceeding great and precious promises; and we can rejoice that "All the promises of God in Him are yea, and in Him Amen, unto the glory of God by us." "The word of the Lord endureth forever."