Judges 11:9

‘ And Jephthah said to the elders of Gilead, “If you bring me home again to fight with the children of Ammon, and Yahweh deliver them before me, shall I be your head?”

Jephthah wanted to be quite clear about what they were offering. He had had no reason to trust them in the past. Why should he trust them now? But his reply demonstrated that in spite of his way of life, he trusted in Yahweh. His faith had been tested in the fires of affliction, and in his military way of life, and now he recognised that in order to obtain victory he would need Yahweh's help. But his reply also gave them comfort. If Yahweh did give him victory, surely this would prove that Yahweh was satisfied for him to be their head. And if not, well, what had they lost?