Jdg 11:30-31
Before commencing the war, however, he vowed a vow to the Lord: “If Thou givest the Ammonites into my hand, he who cometh to meet me out of the doors of my house, when I return safely (in peace, shalom) from the Ammonites, shall belong to the Lord, and I will offer him for a burnt-offering.” By the words אשׁר היּוצא, “he that goeth out,” even if Jephthah did not think “only of a man, or even more definitely still of some one of his household,” he certainly could not think in any case of a head of cattle, or one of his flock. “Going out of the doors of his house to meet him” is an expression that does not apply to a herd or flock driven out of the stall just at the moment of his return, or to any animal that might possibly run out to meet him. For the phrase לקראת יצא is only applied to men in the other passages in which it occurs.
Moreover, Jephthah no doubt intended to impose a very difficult vow upon himself. And that would not have been the case if he had merely been thinking of a sacrificial animal. Even without any vow, he would have offered, not one, but many sacrifices after obtaining a victory.
If therefore he had an animal sacrifice in his mind, he would certainly have vowed the best of his flocks. From all this there can be no doubt that Jephthah must have been thinking of some human being as at all events included in his vow; so that when he declared that he would dedicate that which came out of his house to meet him, the meaning of the vow cannot have been any other than that he would leave the choice of the sacrifice to God himself. “In his eagerness to smite the foe, and to thank God for it, Jephthah could not think of any particular object to name, which he could regard as great enough to dedicate to God; he therefore left it to accident, i.e., to the guidance of God, to determine the sacrifice. He shrank from measuring what was dearest to God, and left this to God himself” (P. Cassel in Herzog's Real-encycl.). Whomsoever God should bring to meet him, he would dedicate to Jehovah, and indeed, as is added afterwards by way of defining it more precisely, he would offer him to the Lord as a burnt-offering. The ו before העליתיהוּ is to be taken as explanatory, and not as disjunctive in the sense of “or,” which ו never has. But whether Jephthah really thought of his daughter at the time, cannot be determined either in the affirmative or negative. If he did, he no doubt hoped that the Lord would not demand this hardest of all sacrifices.