30 And Jephthah made a vow to the Lord, and said, "If you will give the Ammonites into my hand, 31 then whoever comes out of the doors of my house to meet me, when I return victorious from the Ammonites, shall be the Lord's, to be offered up by me as a burnt offering." 32 So Jephthah crossed over to the Ammonites to fight against them; and the Lord gave them into his hand. 33 He inflicted a massive defeat on them from Aroer to the neighborhood of Minnith, twenty towns, and as far as Abel-keramim. So the Ammonites were subdued before the people of Israel. 34 Then Jephthah came to his home at Mizpah; and there was his daughter coming out to meet him with timbrels and with dancing. She was his only child; he had no son or daughter except her. 35 When he saw her, he tore his clothes, and said, "Alas, my daughter! You have brought me very low; you have become the cause of great trouble to me. For I have opened my mouth to the Lord, and I cannot take back my vow."

Matthew Henry's Commentary on Judges 11:30-35

Commentary on Judges 11:29-40

(Read Judges 11:29-40)

Several important lessons are to be learned from Jephthah's vow. 1. There may be remainders of distrust and doubting, even in the hearts of true and great believers. 2. Our vows to God should not be as a purchase of the favour we desire, but to express gratitude to him. 3. We need to be very well-advised in making vows, lest we entangle ourselves. 4. What we have solemnly vowed to God, we must perform, if it be possible and lawful, though it be difficult and grievous to us. 5. It well becomes children, obediently and cheerfully to submit to their parents in the Lord. It is hard to say what Jephthah did in performance of his vow; but it is thought that he did not offer his daughter as a burnt-offering. Such a sacrifice would have been an abomination to the Lord; it is supposed she was obliged to remain unmarried, and apart from her family. Concerning this and some other such passages in the sacred history, about which learned men are divided and in doubt, we need not perplex ourselves; what is necessary to our salvation, thanks be to God, is plain enough. If the reader recollects the promise of Christ concerning the teaching of the Holy Spirit, and places himself under this heavenly Teacher, the Holy Ghost will guide to all truth in every passage, so far as it is needful to be understood.