Judges 11:9-13
English Standard Version
Chapter 11
9Jephthah said to the elders of Gilead, "If you bring me home again to fight against the Ammonites, and the Lord gives them over to me, I will be your head." 10And the elders of Gilead said to Jephthah, "The Lord will be witness between us, if we do not do as you say." 11So Jephthah went with the elders of Gilead, and the people made him head and leader over them. And Jephthah spoke all his words before the Lord at Mizpah.
12Then Jephthah sent messengers to the king of the Ammonites and said, "What do you have against me, that you have come to me to fight against my land?"
13And the king of the Ammonites answered the messengers of Jephthah, "Because Israel on coming up from Egypt took away my land, from the Arnon to the Jabbok and to the Jordan; now therefore restore it peaceably."