Judges 11:29-40

Then the Spirit of the LORD entered Jephthah. Jephthah passed through Gilead and Manasseh and the city of Mizpah in Gilead to the land of the Ammonites. Jephthah made a promise to the LORD, saying, “If you will hand over the Ammonites to me, I will give you as a burnt offering the first thing that comes out of my house to meet me when I return from the victory. It will be the LORD’s.” Then Jephthah went over to fight the Ammonites, and the LORD handed them over to him. In a great defeat Jephthah struck them down from the city of Aroer to the area of Minnith, and twenty cities as far as the city of Abel Keramim. So the Ammonites were defeated by the Israelites. When Jephthah returned to his home in Mizpah, his daughter was the first one to come out to meet him, playing a tambourine and dancing. She was his only child; he had no other sons or daughters. When Jephthah saw his daughter, he tore his clothes to show his sorrow. He said, “My daughter! You have made me so sad because I made a promise to the LORD, and I cannot break it!” Then his daughter said, “Father, you made a promise to the LORD. So do to me just what you promised, because the LORD helped you defeat your enemies, the Ammonites.” She also said, “But let me do one thing. Let me be alone for two months to go to the mountains. Since I will never marry, let me and my friends go and cry together.” Jephthah said, “Go.” So he sent her away for two months. She and her friends stayed in the mountains and cried for her because she would never marry. After two months she returned to her father, and Jephthah did to her what he had promised. Jephthah’s daughter never had a husband. From this came a custom in Israel that every year the young women of Israel would go out for four days to remember the daughter of Jephthah from Gilead.