GEMARA: When the mishna speaks of one who slaughtered a Paschal lamb on Shabbat for a different purpose, with what precisely are we dealing? If you say we are dealing with one who erred in that he actually thought this was a different offering and not a Paschal offering, learn from it, i.e., from the fact that the offering is disqualified and he is therefore liable to bring a sin-offering, that the erroneous uprooting of the status of an offering constitutes uprooting, even though he had no intention to do so. It would, however, be surprising to find the mishna taking a stand on this issue, as we find elsewhere that it is the subject of an amoraic dispute (Tosafot). Rather, the mishna must certainly be referring to one who intentionally uprooted the animal’s designation as a Paschal lamb and offered it as a different offering.

If so, say the latter clause of the mishna: As for all other offerings that one unwittingly slaughtered on Shabbat for the purpose of a Paschal offering, if they were not fit for the Paschal offering, he is liable to bring a sin-offering. And if they are fit, Rabbi Eliezer deems him liable to bring a sin-offering, whereas Rabbi Yehoshua exempts him. Now if the mishna is referring to one who intentionally uprooted the original designation of the animal, which he knew was not a Paschal offering, what does it matter to me whether the animal was fit or unfit? He certainly does not think that he is performing a mitzva; why then does Rabbi Yehoshua exempt him from bringing a sin-offering?

Rather, it is obvious that we must be dealing with one who erred. But if so, we have a contradiction in the mishna, as the first clause is referring to one who intentionally uprooted the animal’s designation, whereas the latter clause is referring to one who erred about it. Rabbi Avin said: Yes, we must accept this conclusion even though it is unusual: The first clause deals with one who uprooted the animal’s designation, whereas the latter clause deals with one who erred about it.

The Gemara relates that Rav Yitzḥak bar Yosef once found Rabbi Abbahu standing among a multitude [okhlosa] of people, and he said to him: What is the meaning of our mishna? Rabbi Abbahu said to him: The first clause is referring to one who intentionally uprooted the animal’s status, whereas the latter clause is referring to one who erred about it. Rav Yitzḥak bar Yosef learned this statement from him forty times, and it seemed to him as though it were resting in his pouch; i.e., he repeated it many times until the mishna became crystal clear to him and etched in his memory.

The Gemara raises a difficulty with this understanding of the mishna: We learned in the continuation of the mishna that Rabbi Eliezer said to Rabbi Yehoshua: If with regard to the Paschal lamb, which is permitted to be slaughtered on Shabbat for its own purpose, when one changed its purpose he is nevertheless liable, then with regard to other offerings that are forbidden to be slaughtered on Shabbat even for their own purpose, when he changed their purpose is it not right that he should be liable? And if it is so that the two parts of the mishna are not talking about the same case, surely they are not similar and cannot be compared; as the first clause is referring to one who intentionally uprooted the animal’s status, whereas the latter clause is referring to one who erred about it.

The Gemara answers: According to Rabbi Eliezer, who put forward this a fortiori argument, there is no difference, for in his opinion someone who erred while intending to perform a mitzva is liable to bring a sin-offering, even if he made a reasonable mistake. Thus, he does not differentiate between the deliberate uprooting of the animal’s status and the erroneous sacrificing of the offering for a different purpose. The Gemara asks: But according to Rabbi Yehoshua, for whom there is a difference between the two cases, let him answer Rabbi Eliezer in this way, that the first clause of the mishna is referring to one who intentionally uprooted the status of an offering, while the latter clause is referring to one who erred about it. Why does he introduce another factor, that in the first clause he changed the animal’s purpose for something forbidden, whereas in the latter clause he changed it for something permitted?

The Gemara explains that this is what Rabbi Yehoshua said to Rabbi Eliezer: According to me, these cases are not comparable, because the first clause deals with one who intentionally uprooted the animal’s designation, whereas the latter clause deals with one who erred about it. However, even according to you, who do not differentiate in this manner, I can still answer as follows: No, if you say that one is liable if he slaughtered a Paschal lamb for a different purpose, it is because he changed its purpose for something prohibited. But can you say the same thing about other offerings that he slaughtered for the purpose of a Paschal offering and thus changed their purpose for something permitted?

The mishna continues with what Rabbi Eliezer said to Rabbi Yehoshua: Let the communal offerings prove the matter, for they are permitted for slaughter on Shabbat for their own purpose, and nevertheless, one who unnecessarily slaughters different offerings for their purpose is liable. Rabbi Yehoshua said to him: No, if you said this halakha with regard to communal offerings, it is because they have a limit. But can you necessarily say the same thing with regard to the Paschal lamb, which does not have a limit?

The Gemara asks: Is that to say that wherever there is a limit, Rabbi Yehoshua deems liable one who erred while intending to perform a mitzva? But with regard to the circumcision of babies on Shabbat, which has a limit, we nevertheless learned in a mishna that with regard to one who had two babies to circumcise, one of whom he needed to circumcise after Shabbat and one of whom he needed to circumcise on Shabbat, and he forgot and circumcised the one that should have been circumcised after Shabbat on Shabbat, he is liable to bring a sin-offering. This is because he performed the prohibited labor of causing a wound not in the framework of performing a mitzva, as no obligation yet existed to circumcise the child.

If, however, there were two babies, one of whom he needed to circumcise on Shabbat eve, and one of whom he needed to circumcise on Shabbat, and he forgot and circumcised the one that he should have circumcised on Shabbat eve on Shabbat, Rabbi Eliezer deems him liable to bring a sin-offering. As circumcision after its appointed time does not override Shabbat, he has therefore unwittingly violated Shabbat. And Rabbi Yehoshua exempts him. Since he intended to perform a mitzva, and despite his error in fact performed a mitzva, he is exempt from bringing a sin-offering. Thus, we see that even though there is a limit in the case of the babies, Rabbi Yehoshua nevertheless exempts one who errs while intending to perform a mitzva.

Rabbi Ami said: With what are we dealing here? We are dealing with a case where the circumciser first unwittingly circumcised the baby who should have been circumcised on Shabbat eve on Shabbat, when there is still this other baby who should be circumcised on Shabbat with whom he is preoccupied. Since he was legitimately preoccupied with a mitzva, as he knew that there was a baby that needed to be circumcised, he is exempt from bringing a sin-offering. Here, however, with regard to offerings, we are dealing with a case where he first slaughtered the required communal offerings at the beginning, so that there was no need to slaughter any more offerings, as communal offerings have a limit. Since he had no reason to make a mistake, he is liable to bring a sin-offering for having unnecessarily slaughtered an animal on Shabbat.

The Gemara asks: If so, how do we understand the continuation of the mishna, where Rabbi Meir says that according to Rabbi Yehoshua, even one who unwittingly slaughters other offerings for the purpose of communal offerings beyond their daily limit is exempt? According to our explanation, this must be true even though he first slaughtered the required communal offerings at the beginning. But didn’t Rabbi Ḥiyya from the village of Avel Arav teach in a baraita another version of the dispute, according to which Rabbi Meir said: Rabbi Eliezer and Rabbi Yehoshua did not disagree over one who had two babies to circumcise, one to circumcise on Shabbat eve and one to circumcise on Shabbat, and he forgot and circumcised the one who should have been circumcised on Shabbat eve on Shabbat; in that case, everyone agrees that he is liable to bring a sin-offering.

With regard to what did they disagree? With regard to one who had two babies to circumcise, one to circumcise after Shabbat and one to circumcise on Shabbat, and he forgot and circumcised the baby who should have been circumcised after Shabbat on Shabbat, as Rabbi Eliezer deems him liable to bring a sin-offering, and Rabbi Yehoshua exempts him.

The Gemara expresses surprise: And how can you understand this baraita in its current formulation? If there, in the latter clause, where he circumcised the baby who should have been circumcised after Shabbat on Shabbat, so that he did not perform a mitzva because the baby was not yet eight days old and the mitzva did not yet apply, Rabbi Yehoshua nevertheless exempted him because he erred while intending to perform a mitzva. Then where he did perform a mitzva, i.e., where he circumcised a baby on Shabbat who was already eight days old before Shabbat and to whom the mitzva of circumcision applied, would Rabbi Yehoshua deem him liable?

The Rabbis of the school of Rabbi Yannai said: The first clause of the baraita is referring to a unique situation, where the circumciser first unwittingly circumcised on Shabbat eve the baby who should have been circumcised on Shabbat.