Judges 11:38, commentary and pictures

He sent her away for two months, and she went with her companions upon the mountains to bewail her virginity in solitude according to social custom.
Her grief was over lifelong virginity and not approaching death, for she was to remain unmarried and childless, dedicated to the Lord for life and relinquishing all hope of becoming a mother in Israel.
She was not killed as a burnt offering but was doomed to perpetual virginity, set apart for religious duties in an unmarried state, since human sacrifice is offensive to God and prohibited by the law.
What met him was to be the Lord's, or where the law permits to be offered as a burnt offering, so a clean animal would have been sacrificed while a human being was devoted to the Lord's service and he himself would offer a burnt offering to Jehovah.
The account stands as an example of a rash oath whose unforeseen fulfillment brought terrible suffering upon his innocent daughter, and it teaches that a vow does not make an unlawful act obligatory because the sin lies in making an unlawful vow and not in breaking it.

Mourning in the Mountains

Jephthah sent his daughter away for two months, and she went with her companions upon the mountains to bewail her virginity. The two months came after the sending away and before the fulfilling of the vow, a departure in which she mourned her virginity in the mountains with her companions. The mountains gave solitude for lament, and in yielding to social custom she mourned there with her companions.

Her grief was over lifelong virginity and not over approaching death. She was to remain unmarried and childless, dedicated to the Lord for life, relinquishing the hope of becoming a mother in Israel. She was not killed as a burnt offering but was doomed to perpetual virginity, devoted to be the Lord's in His service. Because she was his only child, her remaining unmarried and childless ended all hope of descendants and meant the loss of his posterity, which was counted a great sorrow.

Her loss was the loss of marriage and descendants, of marrying and establishing a household of her own. She would not rank among the mothers of Israel nor become a mother among Israel. She would not be among the ancestors or progenitors of the promised Messiah, ending the hope that the Messiah might come through Jephthah's line. Israel's daughters afterward held an annual mourning recalling her loss, visiting her yearly to show sympathy for her seclusion and to honor her loss and filial obedience.

Vow, Dedication, and Warning

She was not killed as a burnt offering but was doomed to perpetual virginity, devoted to be the Lord's in His service for life, never to marry and never to become a mother in Israel. Her mourning with her companions was for that loss of marriage, motherhood and descendants, which ended all hope of posterity through his only child and ended the hope that the promised Messiah might come through that line. The vow is understood to mean that what met him should be the Lord's, or, where the law permits, should be offered as a burnt offering, so that a clean animal would have been sacrificed, but a human being was set apart for religious duties in an unmarried state, while he himself would offer a burnt offering to Jehovah. Human sacrifice is offensive to God and prohibited by the law, and the priests would not have offered it, so such an impious vow could not have been performed. She was probably devoted instead to lifelong service in the tabernacle, as Hannah dedicated Samuel before birth, remaining unmarried and secluded with no household of her own.

The two-month interval after he sent her away and before the outcome of the vow gave time for the priests to intervene or for release from the vow to be sought, which makes it unlikely that she was sacrificed. The account gives a standing example of a rash oath and its folly, in which unforeseen circumstances made the vow bring terrible suffering upon his innocent daughter. Like Herod's oath to give the daughter of Herodias whatever she asked, it warns against making rash vows or promises. The principle applied to the account is that a vow does not make an unlawful act obligatory: the sin lies in making an unlawful vow, not in breaking it, and God does not accept an act that violates other duties.

Those who held it teach that the passage records devoting his daughter as a sacrifice, and that true history was taken by the heathen and turned into the fable of Agamemnon sacrificing his daughter Iphigenia, as one of many Old Testament events that became the foundation for monstrous stories among the ancients. Those who held it teach that the verse belongs to the account of the godless Jephtha vowing his child on one cast of the dice.