Judges 11:29–40
29 The Spirit of the Lord came on Jephthah, who traveled through Gilead and Manasseh, and then through Mizpah of Gilead. He crossed over to the Ammonites from Mizpah of Gilead. 30 Jephthah made this vowf to the Lord: “If you in fact hand over the Ammonites to me, 31 whoever comes out the doors of my house to greet me when I return safely from the Ammonites will belong to the Lord, and I will offer that person as a burnt offering.”g
32 Jephthah crossed over to the Ammonites to fight against them, and the Lord handed them overh to him. 33 He defeated twenty of their cities with a great slaughter from Aroer all the way to the entrance of Minnith and to Abel-keramim. So the Ammonites were subduedi before the Israelites.
34 When Jephthah went to his home in Mizpah, there was his daughter, coming out to meet him with tambourines and dancing!j She was his only child; he had no other son or daughter besides her. 35 When he saw her, he tore his clothes and said, “No! Not my daughter! You have devastated me! You have brought great misery on me.A I have given my word to the Lord and cannot take it back.”
36 Then she said to him, “My father, you have given your word to the Lord. Do to me as you have said, for the Lord brought vengeance on your enemies, the Ammonites.” 37 She also said to her father, “Let me do this one thing: Let me wander two months through the mountains with my friends and mourn my virginity.”
38 “Go,” he said. And he sent her away two months. So she left with her friends and mourned her virginity as she wandered through the mountains. 39 At the end of two months, she returned to her father, and he kept the vow he had made about her. And she had never been intimate with a man. Now it became a custom in Israel 40 that four days each year the young women of Israel would commemorate the daughter of Jephthah the Gileadite.