Judges 11:35

Jephthah was right in not being deterred from keeping his vow by the loss and sorrow to himself (compare the marginal references), just as Abraham was right in not withholding his son, his only son, from God, when commanded to offer him up as a burnt-offering. But Jephthah was wholly wrong in that conception of the character of God which led to his making the rash vow. And he would have done right not to slay his child, though the guilt of making and of breaking such a vow would have remained. Josephus well characterizes the sacrifice as “neither sanctioned by the Mosaic law, nor acceptable to God.”