Study Bava Batra folio 126B with parallel Hebrew-English text, traditional commentary, and modern study tools. Free access to Babylonian Talmud online.
Rav Pappi and Rav Pappa disagree with regard to Rava’s intention. One Sage, Rav Pappi, holds that he has done nothing with regard to his brother’s portion, as he had no right to sell it; with regard to his own additional portion, the sale was valid, as it was in his possession even before the divi
The Talmud notes that they sent a ruling from there, Eretz Yisrael: A firstborn who sold his additional portion before the division of the property has done nothing. Apparently, the rabbis of Eretz Yisrael hold that a firstborn does not have a right to his additional portion before the division. B
The Talmud relates: Mar Zutra of the house of Rishba, who was a firstborn, divided a basket of peppers from the estate of his father with his brothers equally. He came before Rav Ashi to claim a double portion of the rest of the estate. Rav Ashi said to him: Since you relinquished your additional
Mishnah: In a case of one who says: So-and-so, my firstborn son, will not take a double portion of my estate; or one who says: So-and-so, my son, will not inherit my estate among his brothers, he has said nothing, as he has stipulated counter to that which is written in the Torah.
With regard to one on his deathbed who apportions his property orally, granting it to his sons as a gift, and he increased the portion given to one of his sons and reduced the portion given to one son, or equated the portion of the firstborn to the portions of the other sons, his statement stands.