מַאי שְׁנָא מָעוֹת דְּלָא דְּלָאו הָנֵי מָעוֹת שְׁבַק אֲבוּהוֹן קַרְקַע נָמֵי לָאו הָא קַרְקַע שְׁבַק אֲבוּהוֹן because what is different about money, resulting in the halakha that the firstborn is not entitled to a double portion of it, is that their father did not leave them this specific money that was collected. With regard to land as well, their father did not leave them this specific parcel of land when he died, as the debtor could have repaid them with a different parcel of land, or with money.
וְעוֹד הָא אַתְּ הוּא דְּאָמְרַתְּ מִסְתַּבֵּר טַעְמָא דִּבְנֵי מַעְרְבָא דְּאִי קְדֵים סָבְתָּא וְזַבְּנָא זְבִינַהּ זְבִינֵי And furthermore, aren’t you the one who said that the explanation of the people of the West, Eretz Yisrael, is reasonable? In a case where a married woman had been fit to inherit from her great-grandmother but then predeceased her great-grandmother, who then died, and her widower claims the inheritance in his late wife’s stead, the Sages of Eretz Yisrael ruled that he is not entitled to the inheritance, as it is merely property due to his wife, and a husband does not inherit property due to be inherited by his late wife. Rabba agreed that the inheritance is considered property due to the wife, and not property possessed by her, as if the great-grandmother would have sold it before she died, her sale would have been a valid sale. Here, too, the land should be considered property due to the father, of which a firstborn is not entitled to a double portion, since the debtor could have sold it. Therefore, Rabba’s opinion is difficult.
לְרַב נַחְמָן קַשְׁיָא מַאי שְׁנָא קַרְקַע דְּלָא דְּלָאו הָא קַרְקַע שְׁבַק אֲבוּהוֹן מָעוֹת נָמֵי לָאו הָנֵי מָעוֹת שְׁבַק אֲבוּהוֹן Abaya continues: According to the opinion of Rav Naḥman it is difficult; what is different about land, resulting in the halakha that the firstborn is not entitled to a double portion of it, is that their father did not leave them this specific parcel of land. With regard to money as well, their father did not leave them this specific money when he died.
וְעוֹד הָא אָמַר רַב נַחְמָן אָמַר רַבָּה בַּר אֲבוּהּ יְתוֹמִים שֶׁגָּבוּ קַרְקַע בְּחוֹבַת אֲבִיהֶן בַּעַל חוֹב חוֹזֵר וְגוֹבָהּ מֵהֶן And furthermore, doesn’t Rav Naḥman say that Rabba bar Avuh says: With regard to orphans who collected land for a debt owed to their father, their father’s creditor can come and seize this land from them, as any land owned by the father is liened against his debts. Evidently, Rav Naḥman holds that land liened against a debt has the legal status of land that is in the possession of the creditor. If so, why does Rav Naḥman hold that a firstborn is not entitled to a double portion of land that is collected as payment of a debt?
אֲמַר לֵיהּ לָא לְדִידִי קַשְׁיָא וְלָא לְרַב נַחְמָן קַשְׁיָא טַעְמָא דִּבְנֵי מַעְרְבָא קָאָמְרִינַן וְלַן לָא סְבִירָא לַן Rabba said to Abaye: According to my opinion it is not difficult, and according to the opinion of Rav Naḥman it is not difficult. We were merely saying, i.e., explaining, the reason for the opinion of the people of the West, Eretz Yisrael, introduced with the phrase: They sent the following ruling from there, that a firstborn is entitled to a double portion of the payment of a debt. But we ourselves do not hold in accordance with that opinion. Therefore, one cannot raise a contradiction from our opinions stated elsewhere to what we said in explanation of the Sages of Eretz Yisrael.
מַאי סָבְתָּא דְּהַהוּא דַּאֲמַר לְהוּ Having mentioned in passing the case of the great-grandmother, the Gemara discusses that case in depth. What is the case of the great-grandmother that was mentioned by Abaye? The Gemara explains: There was a certain moribund person who said to those present: