Ketubot, Chapter One, Mishnah Six
Our mishnah begins a series of debates between Rabban Gamaliel, Rabbi Eliezer and Rabbi Joshua over the credibility of certain legal claims that a woman might make. Our mishnah deals with virginity claims, the main topic of the chapter.
If a man marries a woman and does not find her to be a virgin:
She says, After you betrothed me I was raped, and so your field has been washed away
And he says, No, rather [it occurred] before I betrothed you and my acquisition was a mistaken acquisition
Rabban Gamaliel and Rabbi Eliezer say: she is believed.
Rabbi Joshua says: We do not live by her mouth, rather she is in the presumption of having had intercourse before she was betrothed and having deceived him, until she brings proof for her statement.
In the scenario in our mishnah, a man comes to court after the first night with his wife and claims that she was not a virgin. She responds by admitting that she was not a virgin, but counter-claims that she had lost her virginity by being raped and that the rape had occurred after her betrothal. Both of these claims are essential to her defense. The fact that the intercourse took place after betrothal means that she did not deceive him by allowing him to betroth her under the false precept that she was a virgin. The fact that she had sexual intercourse unwillingly is essential if she wishes not to be considered an adulteress. If she had intercourse with someone other than her husband after the betrothal she would be an adulteress and as such she would not receive her ketubah. If the court believes both of her claims, then she would receive her ketubah. Note that the mishnah uses a metaphor for the woman: she is a field whose top, fertile layer has been swept away, causing a loss to the man. The comparison of women to fields or houses, as bothersome as it might be to our modern ears, is not uncommon in rabbinic literature.
The husband counterclaims that she had relations before betrothal, and that he acquired her under the mistaken assumption that she was a virgin. It is unclear whether or not he wishes to pay her a ketubah of 100 or he wishes to be totally exempt from paying her a ketubah. What is clear is that the dispute in this mishnah is financial: she wishes to receive her full ketubah and he wishes to lessen his payment.
Rabban Gamaliel and Rabbi Eliezer rule that the woman is believed and that she receives a ketubah of 200 zuz. The talmud explains that since the woman is certain in her claim, whereas the man does not really know when she lost her virginity, she is believed.
Rabbi Joshua says she is not believed until she can bring proof to back up her words. The talmud explains that Rabbi Joshua reasons that since this is a monetary case, and we generally hold that in monetary cases the burden of proof is on the party which wishes to extract money from the other party, in this case the burden of proof is upon her. In order to extract her ketubah money from him she must prove that she was a virgin at the time of betrothal.