The Gemara asks: The halakha that one who acts unawares is exempt is stated in which case? If you say it applies to the cases of forbidden fats and those with whom intercourse is forbidden this cannot be correct, as in those cases one who acts unawares is liable to bring a sin offering. As Rav Naḥman says that Shmuel says: With regard to one who acts unawares and transgresses the prohibitions of eating forbidden fats or engaging in intercourse with those with whom intercourse is forbidden, he is liable to bring a sin offering because he derived pleasure.

And if you say it is referring a case of one who acts unawares on Shabbat this cannot be correct either, as it is already established that one who acts unawares on Shabbat is exempt. What is the reason? The Torah prohibited only planned, constructive labor on Shabbat. Acts of labor that are not intended, or whose result is unintended, or whose consequence is destructive, are not included in this category. Therefore, it is already a known halakha that one who performs labor unawares on Shabbat is exempt.

The Gemara answers: According to Rava, you find it is necessary to teach that one is exempt from bringing a sin offering for performing labor unawares on Shabbat in a case where one intended to cut a detached plant and he mistakenly cut a plant still attached. According to Abaye, who maintains he is liable in such a case, you find it necessary to teach that one who acts unawares is exempt in a case where he intended to lift a plant detached from the ground and mistakenly cut a plant still attached to the ground.

As it was stated: With regard to one who intended to lift a plant detached from the ground and mistakenly cut a plant still attached to the ground, all agree he is exempt from bringing a sin offering. What is the reason? It is due to the fact that he did not intend to act for the sake of cutting, i.e., he merely intended to lift the plant. By contrast, if one intended to cut a detached plant and he mistakenly cut a plant that is still attached, Abaye said he is liable, due to the fact that he intended to act for the sake of cutting. Although his intention was not to perform a prohibited cutting, nevertheless he had intent to cut, and therefore he is liable for the prohibited cutting he performed in practice. Rava said: He is exempt, due to the fact that he did not intend to perform a prohibited cutting.

§ The mishna teaches that Rabbi Yosei says: Rabbi Eliezer and Rabbi Yehoshua did not disagree with regard to one who performs prohibited labor during the intervening twilight period; rather, they both agree that he is exempt, as I say: He performed part of the labor today and he performed part of the labor the following day. It is taught in a baraita that Rabbi Yosei said to the other Sages: You were diligent to examine my opinion, and you found a refutation of my statement.

The Gemara asks: What did they say to him that led Rabbi Yosei to say to them: You were diligent to examine my opinion? The Gemara explains that this is what they said to him: What is the halakha in a case where one lifted an item at twilight between Shabbat and Yom Kippur and carried it from one domain to another? If the domains are adjacent, this act can be performed so quickly that even at twilight it does not span two days. For this reason, Rabbi Yosei said to them: You were diligent to examine my opinion.

Since according to Rabbi Yosei the period of twilight is instantaneous, the Gemara objects: But let him say to them: In this case as well, part of the lifting was performed today and part of it was performed tomorrow. The Gemara explains: That is also what he is saying to them: You were diligent to examine my opinion, and yet you have not accomplished anything, as I remain steadfast in my opinion.

The Gemara objects: And according to Rabbi Yosei, had the start of the labor been on Shabbat and the completion of the labor on Yom Kippur, Rabbi Eliezer and Rabbi Yehoshua would agree that he is exempt. But according to Rabbi Eliezer, would he really be exempt? Didn’t we hear that Rabbi Eliezer deems one liable for the final stage of a prohibited labor? As we learned in a mishna (Shabbat 105a) that Rabbi Eliezer says: One who weaves on Shabbat is liable to bring a sin offering if he weaves three threads at the beginning of work on a new item, or if he adds one thread to a preexisting woven fabric. Although the minimum number of threads required for the prohibited labor of weaving is generally three, Rabbi Eliezer deems one liable for a single thread that he adds to a woven fabric.

Rav Yosef said in response: Rabbi Yosei, in accordance with the opinion of Rabbi Eliezer, would explain that this is what the mishna teaches: Rabbi Eliezer says: One who weaves on Shabbat is liable if he weaves three threads at the beginning of work on a new item, or if he adds two threads to a preexisting woven fabric.

§ The mishna teaches that Rabbi Yehuda said: Rabbi Yehoshua would deem exempt one who does not know the nature of his sin even from bringing a provisional guilt offering. It is taught in a baraita that Rabbi Yehuda said: Rabbi Yehoshua would deem exempt one who does not know the nature of his sin even from bringing a provisional guilt offering, as it is stated: “And if anyone sin, and do any of the commandments of the Lord that are not to be done, though he does not know it; yet is he guilty, and shall bear his iniquity” (Leviticus 5:17). The verse excludes this case, where he knew that he sinned. Rabbi Shimon said to Rabbi Yehuda: It can be inferred from this same verse that he does in fact bring a provisional guilt offering. The phrase “and do…though he does not know it” indicates that one brings an offering in a case such as this, when he did not know with which item he sinned.

The baraita continues: But in a case where there is uncertainty whether one ate forbidden fat and uncertainty whether one did not eat forbidden fat, which is a situation where he did not know if he sinned at all, it is unclear whether Rabbi Shimon maintains he is liable to bring a provisional guilt offering. Therefore, go and ask about it, to determine whether one brings a provisional guilt offering in such a case or not. The Gemara asks: What conclusion was reached about it?

The Gemara suggests: Come and hear a proof from a baraita: If one sinned and did not know with what item he sinned, or if there is uncertainty whether he sinned and uncertainty whether he did not sin, he brings a provisional guilt offering. The Gemara infers: Whom did you hear who says that if one sinned and did not know with what item he sinned he must bring a provisional guilt offering? It is Rabbi Shimon. Consequently, this baraita must be in accordance with his opinion, and it teaches: If there is uncertainty whether one sinned and uncertainty whether one did not sin, he brings a provisional guilt offering. Conclude from the baraita that Rabbi Shimon holds: If there is uncertainty if one sinned and uncertainty if one did not sin, he brings a provisional guilt offering.

§ The mishna teaches that Rabbi Shimon and Rabbi Shimon Shezuri say: Rabbi Eliezer and Rabbi Yehoshua did not disagree with regard to a case where his lack of knowledge involves items from one category. And the last clause in the mishna concludes: If it is so, what is the meaning when the verse states: “If his sin, wherein he has sinned” (Leviticus 4:23), from which it is derived that one is liable only if the object of the sin was the one he intended? It serves to exclude one who acts unawares and does not intend to perform a prohibited action at all.

In connection to this halakha about one who acts unawares, Rav Naḥman says that Shmuel says: With regard to one who acts unawares and transgresses the prohibitions of eating forbidden fats or engaging in intercourse with those with whom intercourse is forbidden, he is liable to bring a sin offering because he derived pleasure from his actions. By contrast, one who acts unawares and performs a prohibited labor on Shabbat is exempt, as the Torah prohibited only planned, constructive labor on Shabbat, which does not include an act of labor that is not intended, or whose result is unintended.

Rava said to Rav Naḥman: But isn’t the case of the two babies considered like a case where one acts unawares, and yet we learned in a mishna (Shabbat 137a): In the case of one who had two babies to circumcise, one of whom he was required to circumcise on Shabbat and one whom he was required to circumcise the day after Shabbat, and he forgot and circumcised the one that should have been circumcised after Shabbat on Shabbat, Rabbi Eliezer deems him liable to bring a sin offering, as circumcision before its appointed time does not override Shabbat. And Rabbi Yehoshua deems him exempt from bringing a sin offering.

Rava explains his objection: Rabbi Yehoshua deemed him exempt only here, in that particular case, because he holds that if one erred with regard to a mitzva and did not perform the mitzva but committed a transgression instead, he is exempt. But in a case where one acts unawares in a matter that does not involve a mitzva, even Rabbi Yehoshua deems him liable. This indicates that according to both opinions, in general one who commits a transgression on Shabbat while acting unawares is liable.

Rav Naḥman said to Rava: Leave aside the case of the babies. No proof can be derived from there, as the transgression in that case is the act of inflicting a wound on Shabbat. This is an exceptional case, since one who inflicts a destructive wound is liable despite the fact that one is usually exempt from liability if he performs perform non-constructive acts on Shabbat. Consequently, the standard requirement of constructive labor on Shabbat does not apply, which is why one who acts unawares and inflicts a wound is also liable.

The Gemara cites another difficulty with regard to the claim that one who acts unawares when he performs a labor on Shabbat is exempt. Rav Yehuda raised an objection to Shmuel from the mishna. Rabbi Yehuda says: Even if one intended to pick figs and he picked grapes, or to pick grapes and he picked figs, or to pick black figs and he picked white figs, or to pick white figs and he picked black figs, Rabbi Eliezer deems him liable to bring a sin offering and Rabbi Yehoshua deems him exempt.

Rav Yehuda explained his objection: And this case here is concerning one who acts unawares, and yet not only does Rabbi Eliezer deem him liable, but Rabbi Yehoshua too deemed him exempt from bringing a sin offering only if he unwittingly switched one type for another type, e.g., grapes for figs, or white figs for black figs. But in a case where he unwittingly switches one for another within one type, even Rabbi Yehoshua deems him liable.

Shmuel said to Rav Yehuda in response: Large-toothed one [shinnana], leave the mishna and follow after me, i.e., it should not be understood as you think. What are we dealing with here? We are dealing with a case where the picker lost his train of thought. He had initially intended to pick grapes and then he forgot his initial intention and thought: It is figs that I want. But his hand unwittingly went among the grapes and he picked the grapes he had initially intended. In that case Rabbi Eliezer holds he is liable, as his initial intention was fulfilled. And Rabbi Yehoshua holds f his current intention and thought are not fulfilled, and therefore he is exempt. By contrast, in a standard case where one acts unawares, both agree that he is exempt.