Judges 11 39
When the two months were over, she returned to her father, and he did to her as he had promised, and she was a virgin. This is the origin of the custom in Israel
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CSB Judges 11:39At 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
NAS Judges 11:39And 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,
KJV Judges 11:39And it came to pass at the end of two months, that she returned unto her father, who did with her according to his vow which he had vowed: and she knew no man. And it was a custom in Israel,