Bava Batra — Daf 49a

אין נאמנים מודעא היו דברינו אין נאמנין

הני מילי על פה דלא אתי על פה ומרעא לשטרא אבל בשטרא אתי שטרא ומרעא לשטרא

גופא אמר רב נחמן אמנה היו דברינו אין נאמנין מודעא היו דברינו אין נאמנין

ומר בר רב אשי אמר אמנה היו דברינו אין נאמנין מודעא היו דברינו נאמנין מאי טעמא שזה ניתן ליכתב וזה לא ניתן ליכתב:

ולא לאיש חזקה בנכסי אשתו וכו': פשיטא כיון דאית ליה לפירא פירא הוא דקאכיל

לא צריכא דכתב לה דין ודברים אין לי בנכסייך

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

אמרי לה דבי רבי ינאי מתניתין בכותב לה ועודה ארוסה וכדרב כהנא דאמר רב כהנא

accepted. Also if the witnesses to a deed [of sale] say, We only wrote [under reservation of] a moda'ah  their word is not accepted!  — This is the case where they make a verbal statement to this effect, because a verbal statement cannot invalidate a written deed, but if they write a deed,  then one deed can invalidate another. The preceding text states that R. Nahman said: If the witnesses [to a bond] say, We only wrote it [under cover of] an amanah, their word is not accepted, and if the witnesses [to a deed] say, We wrote [it under the reservation of] a moda'ah, their word is not accepted. Mar son of R. Ashi, however, says that if they say, We only wrote [it] under cover of an amanah, their word is not accepted, but if they say, We wrote [under the reservation of] a moda'ah, their word is accepted. The reason is that it is proper to commit to writing a moda'ah, but it is not proper to commit to writing an amanah. THE HUSBAND HAS NO HAZAKAH IN THE PROPERTY OF HIS WIFE. Surely this is self-evident? Since he has a right to the produce [of the wife's field,  therefore, however long he occupies it we say that] he is merely taking the produce?  — The rule required to be stated for the case in which he has made a written declaration that he has no right or claim to her property.  But suppose he has done so, what difference does it make, seeing that it has been taught, If a man says to another, I have no right or claim to this field, I have no concern in it, I totally dissociate myself from it, his words are of no effect?  — In the school of R. Jannai the answer was given that the Mishnah here [is referring to the case] where the husband made this declaration to the wife while she was still only betrothed to him; [and such a declaration would be valid] in virtue of the dictum of R. Kahana