Judges 11:9-11

Jephthah said to the elders, “Let me get this straight. If I come with you and if the LORD gives me victory over the Ammonites, will you really make me ruler over all the people?” “The LORD is our witness,” the elders replied. “We promise to do whatever you say.” So Jephthah went with the elders of Gilead, and the people made him their ruler and commander of the army. At Mizpah, in the presence of the LORD, Jephthah repeated what he had said to the elders.