אין נאמנים מודעא היו דברינו אין נאמנין
they are not deemed credible. And similarly, witnesses who said: Our statement that we signed was accompanied by a preemptive declaration, are not deemed credible. They cannot negate the testimony of the document that they themselves signed by claiming that there had been a preemptive declaration. Similarly, how could Rabba bar bar Ḥana’s signing of the preemptive declaration override his signing the bill of sale?
הני מילי על פה דלא אתי על פה ומרעא לשטרא אבל בשטרא אתי שטרא ומרעא לשטרא
The Gemara answers: That matter of witnesses not being deemed credible to nullify a document applies only when the witnesses attempt to nullify the document by means of an oral declaration, as an oral declaration cannot come and weaken a written document. But if the witnesses attempt to nullify the bill of sale by means of testimony in another document, e.g., by signing the preemptive declaration, then this preemptive document can come and weaken a written document, in this case, the bill of sale.
גופא אמר רב נחמן אמנה היו דברינו אין נאמנין מודעא היו דברינו אין נאמנין
The Gemara returns to discuss the matter itself: Rav Naḥman says that witnesses who said: Our statement that we signed was a document of trust, are not deemed credible. And similarly, witnesses who said: Our statement that we signed was accompanied by a preemptive declaration, are not deemed credible.
ומר בר רב אשי אמר אמנה היו דברינו אין נאמנין מודעא היו דברינו נאמנין מאי טעמא שזה ניתן ליכתב וזה לא ניתן ליכתב:
And Mar bar Rav Ashi says that witnesses who said: Our statement that we signed was a statement of trust, are not deemed credible; but witnesses who said: Our statement that we signed was accompanied by a preemptive declaration, are deemed credible. What is the reason for the difference between the cases? The reason is that this document that was accompanied by a preemptive declaration may be written, as it is merely written under duress, but that document of trust may not be written, as it is a false document. Testifying that they wrote it is self-incriminating, and the witnesses are not deemed credible to incriminate themselves.
ולא לאיש חזקה בנכסי אשתו וכו': פשיטא כיון דאית ליה לפירא פירא הוא דקאכיל
§ The mishna teaches that a man does not have the ability to establish the presumption of ownership with regard to his wife’s property and a wife does not have the ability to establish the presumption of ownership with regard to her husband’s property. The Gemara asks: Isn’t this obvious? Since he has the right to enjoy the profits of her property while they are married, it is known that he is only enjoying the profits and that he has no claim to the field itself. On what grounds, then, would he establish the presumption of ownership?
לא צריכא דכתב לה דין ודברים אין לי בנכסייך
The Gemara responds: No, it is necessary to teach this halakha in a case where the husband wrote to his wife: I do not have any legal dealings or involvement with your property, i.e., he forfeits his right to enjoy the profits of her property, and therefore if he subsequently did enjoy the profits of her field, one might assume that it is because he acquired the land from her. It was therefore necessary for the mishna to teach that this does not indicate that he owns the land, since it is possible that she does not prevent him from enjoying the profits, due to their relationship.
וכי כתב לה מאי הוי והתניא האומר לחבירו דין ודברים אין לי על שדה זו ואין לי עסק בה וידי מסולקות ממנה לא אמר כלום
The Gemara asks: And if he wrote this to her, what of it? And isn’t it taught in a baraita: One who says to another: I do not have any legal dealings or involvement concerning this field, or: I have no dealings with it, or: My hands are removed from it, has not said anything. That is to say, these statements have no legal standing.
אמרי לה דבי רבי ינאי מתניתין בכותב לה ועודה ארוסה וכדרב כהנא דאמר רב כהנא
The scholars of the school of Rabbi Yannai said with regard to this: The mishna states its ruling with regard to one who writes this formulation to her while she is still only betrothed, before he had any rights to her property. Therefore, he is able to prevent his rights from taking effect after the marriage. And this is in accordance with the statement of Rav Kahana, as Rav Kahana says: