"Then it shall be, that whatsoever cometh forth of the doors of my house to meet me, when I return in peace from the children of Ammon, shall surely be the LORD's, and I will offer it up for a burnt offering." (Judges 11:31)
The story of Jephthah has been a stumbling block to many who interpret it as teaching that Jephthah sacrificed his daughter to God as a burnt offering. As Jephthah was preparing to face the Ammonite armies, he had made the vow recorded in our text, if God would only give him the victory. His only child--a beloved daughter--was then first to meet him at his return, and so it was she who had to be offered.
It should be remembered, however, that Jephthah was a man of true faith (Hebrews 11:32-33), and he would never have vowed to disobey God's prohibition against human sacrifice. The problem is that the Hebrew conjunction waw (translated "and" in our text) is very flexible in meaning depending on context. Here, "or" is better than "and."
That is, Jephthah vowed that whatever first came out to meet him would be dedicated to the Lord: if a person came out (Jephthah was probably thinking of a servant), he or she would be dedicated to God's service at the tabernacle, as Hannah later dedicated Samuel (1 Samuel 1:11). Or if an animal from his flock came out, it would be sacrificed.
His daughter, out of love for her father and gratitude to God for His deliverance from the Ammonites, insisted that her father keep his vow. Since that meant that she, as a perpetual servant at the tabernacle, could never have a husband and children, she "bewailed her virginity" for two months (not her impending death) and then "returned to her father," so that he could keep his vow, and throughout her life "she knew no man" (Judges 11:38-39). Instead of a strange tale of human sacrifice, this is the story of the love of a God-fearing father and daughter for each other and for their Lord. HMM