She said to him, My father, you have opened your mouth to Yahweh; do to me according to that which has proceeded out of your mouth, because Yahweh has taken vengeance for you on your enemies, even on the children of Ammon.
Jephthah believed he could not get out of his vow (Judges 11:35). Unfortunately he did not know, or had forgotten, that God had made provision for His people to redeem things they had vowed to give Him. Leviticus 27:1-8 told the Israelites that if they vowed someone or something to God and then wanted it back they could pay a stated ransom price and buy it back. Had he obeyed the Word of God he could have avoided sacrificing his daughter. With his vow he sought to secure his present, but through it he ended up sacrificing his future. Contrast the outcome of Abraham’s sacrifice of Isaac (Genesis 22). He secured a hope and a future whereas Jephthah lost both. This is yet another example in Judges of self-assertion leading to violence, in this case the abuse of a young woman.