Judges 11:39-40

New Revised Standard Version, Anglicised

³⁹ At the end of two months, she returned to her father, who did with her according to the vow he had made. She had never slept with a man. So there arose an Israelite custom that ⁴⁰ for four days every year the daughters of Israel would go out to lament the daughter of Jephthah the Gileadite.