Moses in Numbers said that chastity be tested by drinking bitter water and seeing if the woman’s stomach would swell (see Numbers 5:13-22). But, he said Deuteronomy 22 provides the blood-stained sheet from the wedding night as evidence of virginity (cf. Dt 22:14-17).
Deuteronomy 22:13 - 30
ESV - 13 If any man takes a wife and goes in to her and then hates her 14 And accuses her of misconduct and brings a bad name upon her, saying, 'I took this woman, and when I came near her, I did not find in her evidence of virginity.
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