Gittin 48B

״במספר שני תבואות ימכר לך״.

“According to the number of years of the crops he should sell to you” (Leviticus 25:15), meaning that it is not the field itself that is sold, but rather, what is sold is the right to consume the produce for a specific number of years.

מתניתא ⁠– דתניא: בכור נוטל פי שנים בשדה החוזרת לאביו ביובל.

A baraita supports the opinion of Reish Lakish, as it is taught: A firstborn son takes a double portion in a field that returns to his father in the Jubilee Year, i.e., a field that his father sold, and he subsequently died, and the field therefore returns to his sons in the Jubilee Year. The halakha is that a firstborn son receives a double portion only of property that the father possessed at the time of his death, but not of property that was due to the father. If the acquisition of the produce is considered to be like the acquisition of the item itself, then the field the father sold would not be considered to have been in his possession at the time of his death.

אמר אביי, נקטינן: בעל בנכסי אשתו צריך הרשאה.

Abaye said: We have a tradition that a husband requires authorization with regard to his wife’s property, meaning that if there is a legal dispute between the husband and another person with regard to the usufruct property the husband received from his wife, he requires authorization from his wife that he may act on her behalf in order to present himself in court as a litigant. If he does not receive such authorization, the other litigant has the right to claim that he is not legally answerable to the husband, and may insist that the wife come before the court herself. This indicates that the acquisition of the produce is not considered to be like the acquisition of the item itself, and therefore the husband is not the owner of the property.