מאי שנא רישא ומאי שנא סיפא? אמר רב ספרא: כאן — מידיעת שבת הוא פורש, וכאן — מידיעת מלאכה הוא פורש. אמר ליה רב נחמן: כלום פריש משבת אלא משום מלאכות, וכלום פריש ממלאכות אלא משום שבת! אלא אמר רב נחמן: קרבן דחייב רחמנא אמאי — אשגגה. התם חדא שגגה, הכא טובא שגגות הויין.
The Talmud asks: What is different about the former clause, which states that he in only liable to bring one sin-offering for each Shabbat, and the latter clause, which states that he is liable for each and every primary category of labor that he performed? Rav Safra said: Here, where he is unaware that the day was Shabbat, when he realizes that he sinned, it is due to awareness of Shabbat that he desists. When he is told that it was Shabbat, he stops immediately. And here, where he is unaware that the labors are prohibited, it is due to awareness of the labors that he desists. When he is told that this labor is prohibited, he stops immediately. Rav Naḥman said to Rav Safra: Does he desist due to Shabbat for any reason other than because he knows that the labors are prohibited? If he did not know that the labor is prohibited, telling him that it is Shabbat would not cause him to desist. And similarly, does he desist from performing the labors when told that it is prohibited for any reason other than because he knows that it is Shabbat? If he did not know that it was Shabbat, there would be no reason for him to desist from labor. Ostensibly, attributing the distinction between the two parts of the Mishnah to what eventually became known to him in the different cases is incorrect. Rather, Rav Naḥman said: The offering that the Torah obligated him to bring; for what is he so obligated? It is for performing an unwitting transgression. There, where he was unaware that the day was Shabbat, he was unwitting with regard to one matter; here, where he was unaware of the prohibited labors, he was unwitting with regard to multiple matters, and he is liable to bring sin-offerings in accordance with the number of matters of which he was unaware.