Talmud - Bava Batra 126a בבא בתרא קכ״ו א׳

And as for a loan that is with the firstborn, i.e., he had borrowed money from his father, then his father died, it is uncertain whether the payment should be considered property due to the father or property possessed by him. Therefore, the firstborn and his brothers divide the additional portion.

§ With regard to the halakha that the firstborn is not entitled to a double portion of the enhancement of the property resulting from the actions of the heirs, Rav Huna says that Rav Asi says: A firstborn who protested the efforts of enhancing the property before it is divided has protested, and if the brothers use resources from the estate to enhance it against his will, he is entitled to a double portion of the enhanced value.

Rabba said: Rav Asi’s opinion is reasonable in a case where they inherited grapes on a grapevine and the brothers harvested them against the will of the firstborn, or if they inherited olives on olive trees and the brothers harvested them, as in these cases, the produce itself did not change. But if they treaded on them, converting them into wine or oil, even if the firstborn protested their doing so, he is not entitled to a double portion. And Rav Yosef said: Even if they treaded on them, the firstborn is entitled to a double portion.

The Gemara asks: Why is he entitled to a double portion, according to Rav Yosef, even if they treaded on them? Since the brothers transformed the produce, as initially it was in the form of grapes and now it is wine, they have acquired it in the same manner that a thief acquires an item he stole. Therefore, the firstborn should have no share of the enhancement.

The Gemara answers: Rav Yosef did not mean that the firstborn is entitled to a double portion of the enhanced value of the wine. Rather, his intention was the same as that which Rav Ukva bar Ḥama says in a different context, that the ruling is referring to a case where the wine spoiled, its value decreasing to below the initial value of the grapes, in which case the brothers must give the firstborn payment for the damage to his additional portion of the grapes. Here, too, Rav Yosef meant that the brothers must give the firstborn payment for the damage to his grapes.

The Gemara explains: Where, i.e., in what context, was the statement of Rav Ukva bar Ḥama stated? It was in reference to that which Rav Yehuda says that Shmuel says: With regard to a firstborn and an ordinary son whose father left them grapes and they harvested them, or if he left them olives and they harvested them, the firstborn takes a double portion. This is the halakha even if they treaded on them. The Gemara asks: Why is he entitled to a double portion if they treaded on them; initially they were grapes, and now it is wine? Mar Ukva bar Ḥama says: Shmuel did not mean that he is entitled to a double portion of the wine; rather, the reference is to a case where the wine spoiled, its value decreasing to below the initial value of the grapes, in which case the ordinary brother must give the firstborn payment for the damage to his grapes.

§ Rav Asi says: A firstborn who took a portion of the property like that of an ordinary heir has relinquished his right to an additional portion. The Gemara asks: What does it mean that he has relinquished his additional portion? Rav Pappa says in the name of Rava that he has relinquished his additional portion only with regard to that field that was divided, since he did not exercise his right to an additional portion, but he has not relinquished his right to receive an additional portion of the rest of the estate. Rav Pappi says in the name of Rava that he has relinquished his additional portion with regard to all of the property.

The Gemara explains: Rav Pappa says in the name of Rava that he has relinquished his additional portion only with regard to that field that was divided, because he holds that a firstborn does not have a right to his additional portion before the division of the property. And therefore, he has waived his additional portion of what has already reached his possession, namely, the field that was divided, but he has not waived his portion of the other fields of the estate.

And Rav Pappi says in the name of Rava that he has relinquished his additional portion with regard to all of the property, as he holds that a firstborn has a right to his additional portion before the division of the property. And therefore, since he waived his additional portion in this field, he has waived his portion of all of the property.

The Gemara notes: And this dispute of Rav Pappi and Rav Pappa was not stated explicitly; rather, it was stated by inference. As there was a certain firstborn who went and sold his property and the property of his deceased ordinary brother, i.e., their respective portions of their father’s property, before the property was divided. The orphan sons of the ordinary brother went to eat dates from the field that was now in the possession of those purchasers, due to their father’s share in the field. The purchasers hit them, as though they were thieves. The relatives of the orphans said to the purchasers: Not only did you purchase their property illegally, but you now hit them as well? They came before Rava, who said to them: The firstborn has done nothing. His sale was not valid.

Traduction : The William Davidson digital edition of the Koren Noé Talmud, with commentary by Rabbi Adin Even-Israel Steinsaltz.

BavaBatra 126a examines whether a firstborn son receives a double share of estate value increased by heirs, debating grapes, olives, and wine processing cases.