Midrash says otherwise.
Other biblical commentators5 disagree. Though Jephthah was one of the Israelite judges, he was chosen for the position because of his bravery and might, not because of his Torah scholarship—indeed, he was woefully ignorant.6 And though he was not bound whatsoever by the vow he made—as it clearly transgressed the rules of the Torah—he ignorantly went ahead and offered his daughter as a sacrifice.
Had he only consulted with Phinehas , the learned high priest of the time, he would have been informed of his error. But that didn’t happen. Jephthah was too arrogant to travel to Phinehas to receive guidance: “I am the general of the Israelite forces, and I should go to him?!” And Phinehas was too proud to unilaterally go to Jephthah to advise him: “He needs me; why should I make the trip?”
The hubris demonstrated by these two leaders cost an innocent girl her life. According to the Midrash 7 both were punished. Phinehas lost the divine spirit that had hitherto rested upon him. Jephthah became ill, and he lost many of his limbs. Because his limbs were buried in many locations, the Bible says that Jephthah was “buried in the cities of Gilead.”8