Judges 11:37-39

37Then she said to her father, “Let this thing be done for me: let me alone for two months, that I may go and wander on the mountains and bewail my virginity, my friends and I.”

38So he said, “Go.” And he sent her away for two months; and she went with her friends, and bewailed her virginity on the mountains.

39And it was so at the end of two months that she returned to her father, and he carried out his vow with her which he had vowed. She knew no man. And it became a custom in Israel