Megillah 19B

הכתובה בין הכתובים. אמר ליה: הרי אמרו, הקורא במגילה הכתובה בין הכתובים ⁠— לא יצא.

that was written together with the rest of the Writings. Rav Yehuda said to him: The rabbis have said: If one reads from a Megilla that was written together with the rest of the Writings he has not fulfilled his obligation.

אמר רבי חייא בר אבא אמר רבי יוחנן: הקורא במגילה הכתובה בין הכתובים ⁠— לא יצא. ומחו לה אמוחא: בצבור שנו.

R' Ḥiyya bar Abba said that R' Yoḥanan said: If one reads from a Megilla that was written together with the rest of the Writings he has not fulfilled his obligation. But they hit this halakha on its head, i.e., immediately after reporting this ruling they added a qualification that removed much of its force: They taught this halakha only with respect to reading the Megilla for a congregation. An individual who reads the Megilla in private fulfills his obligation even if the Megilla was written together with the rest of the Writings. Only when it is read in public must it be from a Megilla that is a separate scroll.

ואמר רבי חייא בר אבא אמר רבי יוחנן: שיור התפר ⁠— הלכה למשה מסיני. ומחו לה אמוחא: ולא אמרו אלא כדי שלא יקרע.

R' Ḥiyya bar Abba also said that R' Yoḥanan said: The halakha of leaving a space without stitches, i.e., that the parchment sheets of a Torah scroll must not be sewn all the way to the edge, but rather a small margin must be left at the top and at the bottom, is a halakha transmitted to Moses from Sinai, i.e., it was not written in the Torah but was received in the framework of the Oral Law. But they immediately hit this halakha on its head, explaining that this halakha is not due to the special sanctity of a Torah scroll; rather, they said that it is only so that it not rip. If the scroll is wound too forcefully, the sheets of parchment will begin to spread apart since they are not sewn together at their extremities, and the one who is winding will cease to wind it so forcefully. If the stitching went all the way to the end there would be no such warning and the stitches would cause the parchment to rip.