Shabbat 37A

לעולם אימא לך להחזיר תנן, וחסורי מיחסרא והכי קתני: כירה שהסיקוה בקש ובגבבא ⁠— מחזירין עליה תבשיל, בגפת ובעצים ⁠— לא יחזיר עד שיגרוף או עד שיתן את האפר. אבל לשהות ⁠— משהין אף על פי שאינו גרוף ואינו קטום. ומה הן משהין? בית שמאי אומרים: חמין, אבל לא תבשיל. ובית הלל אומרים: חמין ותבשיל. והך חזרה דאמרי לך, לאו דברי הכל היא, אלא מחלוקת בית שמאי ובית הלל, שבית שמאי אומרים: נוטלין ולא מחזירין. ובית הלל אומרים: אף מחזירין.

The Talmud rejects this proof. Actually, you can say that in the first clause of the Mishnah we learned to return and the Mishnah is incomplete. A clause must be added to the Mishnah, and it teaches the following: With regard to a stove that was lit with straw or rakings, one may return a pot of cooked food to it. If it was lit with pomace or with wood, one may not return a pot to it until one sweeps the coals out while it is still day or until one covers the coals with ashes. However, to leave the pot on the flame on Shabbat, one may leave it, even though it is not swept and not covered with ashes. Through this addition, the continuation of the dispute can be understood as follows: And what may they leave? Beit Shammai say: Hot water but not cooked food. And Beit Hillel say: Both hot water and cooked food. Furthermore: And that return that I said to you at the start of the Mishnah is not according to everyone. Rather, it too is subject to a dispute between Beit Shammai and Beit Hillel, as Beit Shammai say: One may remove but not return. And Beit Hillel say: One may even return. The dilemma with regard to the interpretation of the Mishnah has not been resolved.

תא שמע, דאמר רבי חלבו אמר רב חמא בר גוריא אמר רב: לא שנו אלא על גבה, אבל לתוכה ⁠— אסור. אי אמרת בשלמא ״להחזיר״ תנן ⁠— היינו דשני בין תוכה לעל גבה. אלא אי אמרת ״לשהות״ תנן, מה לי תוכה מה לי על גבה? מי סברת רבי חלבו ארישא קאי? אסיפא קאי: ״ובית הלל אומרים אף מחזירין״⁠ — ואמר רבי חלבו אמר רב חמא בר גוריא אמר רב: לא שנו אלא על גבה, אבל תוכה ⁠— אסור.

Come and hear another resolution to this dilemma from that which R' Ḥelbo said that Rav Ḥama bar Gurya said that Rav said: They only taught that placing is permitted with regard to a stove as far as placing a pot atop it is concerned. However, placing a pot inside it is prohibited. Granted, if you say that we learned returning in the Mishnah, that is why there is a halakhic difference between placing a pot inside it and placing a pot atop it. If one returns it on Shabbat, placing it inside a stove that might have burning coals, there is concern that Shabbat would be desecrated. Therefore, it was only permitted to place cooked food atop the stove. However, if you say that we learned leaving in the Mishnah, what is the difference to me whether it is inside the stove and what is the difference to me whether it is atop it? Ultimately, he does nothing on Shabbat with the hot ashes in the stove. The Talmud rejects this proof: Do you think that R' Ḥelbo is referring to the first clause of the Mishnah? No, he is referring to the latter clause of the Mishnah, which states: And Beit Hillel say that one may even return. And with regard to this R' Ḥelbo said that Rav Ḥama bar Gurya said that Rav said: They only taught that one may return the cooked food atop the stove; however, inside it is prohibited. If so, there is still no resolution to the dilemma.