Judges 11:6-10

and they said to Jephthah, “Come and be our leader, that we may fight against the sons of Ammon.”

But Jephthah said to the elders of Gilead, “Did you not hate me and drive me from my father’s house? So why have you come to me now when you are in trouble?”

The elders of Gilead said to Jephthah, “For this reason we have now returned to you, that you may go with us and fight the sons of Ammon, and become our head over all the inhabitants of Gilead.”

So Jephthah said to the elders of Gilead, “If you bring me back to fight against the sons of Ammon and the Lord gives them up to me, will I become your head?”

And the elders of Gilead said to Jephthah, “The Lord is witness between us; be assured we will do as you have said.”