Eruvin 7B

דאי דרב ⁠— קשיא דרב אדרב בתרתי: דאמר רב ירמיה בר אבא אמר רב: מבוי שנפרץ במלואו לחצר, ונפרצה חצר כנגדו ⁠— חצר מותרת ומבוי אסור. ואמאי? ליהוי כמבוי שכלה לרחבה!

For if it is a ruling of Rav, the apparent contradiction between one statement of Rav and another statement of Rav poses a difficulty in two ways. The first is with regard to the fact that this alleyway opens into the public domain on two opposite sides, and the second is based on that which Rav Yirmeya bar Abba said that Rav said: If an alleyway was breached along the entire length of its back wall into a courtyard, and likewise the courtyard was breached opposite it into the public domain, it is permitted to carry in the courtyard, and it is prohibited to carry in the alleyway, since this alleyway is now open on two opposite sides to the public domain. Why should this be the ruling? In this case, let it be like an alleyway that terminates in a backyard, where Rav Yehuda ruled that nothing further is needed to permit carrying.

אמר ליה: אנא לא ידענא, עובדא הוה בדורא דרעותא מבוי שכלה לרחבה הוה, ואתא לקמיה דרב יהודה ולא אצרכיה ולא מידי. ואי קשיא משמיה דרב ⁠— תיהוי משמיה דשמואל, ולא קשיא מידי.

Rav Yosef said to Abaye: I do not know in accordance with which of his teachers Rav Yehuda issued this ruling. All I know is that there was an incident in a shepherds’ village where an alleyway terminated in a backyard, and the matter came before Rav Yehuda for a ruling, and he did not require anything to render it permitted to carry in the alleyway. And if, as you say, it is difficult if we say that he issued his ruling in the name of Rav, let it be suggested that he issued it in the name of his other teacher, Shmuel, and then there will be no difficulty.