אף מוחכרת ומושכרת שבחא דממילא קא אתי דלא חסרי בה מזוני

so too in the case of a cow that was leased or rented, the baraita is referring only to a case where the enhancement came by itself, as the brothers did not lose money for its sustenance, since it was stipulated that the one who rented or leased it would provide its feed.

מני רבי היא דתניא אין בכור נוטל פי שנים בשבח ששבחו נכסים לאחר מיתת אביהן רבי אומר אומר אני בכור נוטל פי שנים בשבח ששבחו נכסים לאחר מיתת אביהן אבל לא בשבח שהשביחו יתומים לאחר מיתת אביהן

§ The Gemara continues its discussion of the baraita. In accordance with whose opinion is the baraita? It is in accordance with the opinion of Rabbi Yehuda HaNasi, as it is taught in a baraita ( Tosefta 7: 4): A firstborn does not take a double portion of the enhancement of the property that occurred after the death of the sons’ father. Rabbi Yehuda HaNasi says: I say that a firstborn does take a double portion of the enhancement of the property that occurred by itself after their father’s death, e. g., the birth of a calf, but not of the enhancement that the orphans caused after their father’s death.

ירשו שטר חוב בכור נוטל פי שנים יצא עליהן שטר חוב בכור נותן פי שנים ואם אמר איני נותן ואיני נוטל רשאי

Rabbi Yehuda HaNasi continues: Therefore, if they inherited a promissory note indicating a debt owed to their father, the firstborn takes a double portion of the money when it is collected, as this is an enhancement to the estate that came by itself. The Gemara adds: In a case where a promissory note emerged against them for their father’s debt, the firstborn gives, i. e., repays, a double portion of the debt. But if he says: I am not giving a double portion of the debt and I am not taking a double portion of the estate, he is permitted to do so, and he is exempt from paying a double portion.

מאי טעמייהו דרבנן אמר קרא לתת לו פי שנים מתנה קרייה רחמנא מה מתנה עד דמטיא לידיה אף חלק בכורה עד דמטיא לידיה

The Gemara asks: What is the reason for the ruling of the Rabbis that the firstborn does not receive a double portion of any enhancements that occur after the death of the father? The verse states: “ Giving him a double portion” (Deuteronomy 21:17); by employing the term“ giving” the Merciful One calls the double portion a gift. Just as a recipient of a gift does not acquire a gift unless it first reaches the possession of the one giving the gift, so too the firstborn does not acquire the portion of the firstborn unless it has reached the possession of the father before he died.

ורבי אומר אמר קרא פי שנים מקיש חלק בכורה לחלק פשוט מה חלק פשוט אף על גב דלא מטא לידיה אף חלק בכורה אף על גב דלא מטא לידיה

And Rabbi Yehuda HaNasi says that the reason for his ruling that a firstborn receives a double portion of the enhancement is that the verse states: “ A double portion” (Deuteronomy 21:17). It juxtaposes the portion of the firstborn to the portion of an ordinary son, in that just as the portion of an ordinary son is inherited even from property that did not reach the father’s possession before he died, so too, the portion of the firstborn is inherited even from property that did not reach the father’s possession before he died.

ורבנן נמי הכתיב פי שנים ההוא למיתבא ליה אחד מצרא

The Gemara asks: And according to the Rabbis as well, isn’t the phrase“ a double portion” written? The Gemara answers: That phrase can be said to teach a different halakha, requiring the brothers to give the firstborn both of his portions on one border, i. e., adjoining, and not in separate locations.

ורבי נמי הכתיב לתת לו ההוא שאם אמר איני נוטל ואיני נותן רשאי

The Gemara asks: And according to Rabbi Yehuda HaNasi as well, isn’t the phrase“ giving him” written? The Gemara answers: That phrase can be said to teach a different halakha, that if the firstborn says: I am not taking a double portion of the estate and I am not giving a double portion of the debt, he is permitted to do so. Since the inheritance is referred to as a gift, he has the right to refuse it.

אמר רב פפא דיקלא ואלים ארעא ואסיק שירטון דכולי עלמא לא פליגי דשקיל כי פליגי בחפורה והוה שובלי שלופפי והוו תמרי דמר סבר שבחא דממילא ומר סבר אישתני

The Gemara discusses several types of enhancement. Rav Pappa says: With regard to a palm tree that became enhanced by growing broader after the father’s death, or land that yielded silt and thereby became enhanced, everyone agrees that the firstborn takes a double portion of the enhancement. When they disagree is in a case when fodder [baḥafura], i. e., grain that has grown stalks but is not yet ripe, becomes full ears, of grain, and when date flowers [shelofafei] become fully developed dates. As one Sage, Rabbi Yehuda HaNasi, holds that since this enhancement develops by itself, the firstborn is entitled to a double portion of it, and one Sage, the Rabbis, holds that since the item transformed, it is not considered the same item that was in the father’s possession, and the firstborn is not entitled to a double portion of it.

אמר רבה בר חנא אמר רבי חייא עשה כדברי רבי עשה כדברי חכמים עשה

§ Rabba bar Ḥana says that Rabbi Ḥiyya says: A judge who acted, i. e., ruled, in accordance with the statement of Rabbi Yehuda HaNasi has acted legally, and one who acted in accordance with the statement of the Rabbis has also acted legally. Either way, the decision stands.