Judges 11:30-39

³⁰And Jephthah made a vow to the Lord and said, “If You will indeed hand over to me the sons of Ammon, ³¹then whatever comes out the doors of my house to meet me when I return safely from the sons of Ammon, it shall be the Lord’s, and I will offer it up as a burnt offering.” ³²So Jephthah crossed over to the sons of Ammon to fight against them; and the Lord handed them over to him. ³³He inflicted a very great defeat on them from Aroer to the entrance of Minnith, twenty cities, and as far as Abel-keramim. So the sons of Ammon were subdued before the sons of Israel.

³⁴But Jephthah came to his house at Mizpah, and behold, his daughter was coming out to meet him with tambourines and with dancing. And she was his one and only child; besides her he had no son or daughter. ³⁵So when he saw her, he tore his clothes and said, “Oh, my daughter! You have brought me disaster, and you are among those who trouble me; for I have given my word to the Lord, and I cannot take it back.” ³⁶So she said to him, “My father, you have given your word to the Lord; do to me just as you have said, since the Lord has brought you vengeance on your enemies, the sons of Ammon.” ³⁷And she said to her father, “Let this thing be done for me; allow me two months, so that I may go to the mountains and weep because of my virginity, I and my friends.” ³⁸Then he said, “Go.” So he let her go for two months; and she left with her friends, and wept on the mountains because of her virginity. ³⁹And at the end of two months she returned to her father, who did to her what he had vowed; and she had no relations with a man. And it became a custom in Israel,