[Ulla explained the dispute in terms of whether it was likely that witnesses would appear to testify that the woman was guilty of a capital crime. The Sages saw this as a real possibility, and thus required a court of twenty-three {since there was a potential capital offense}; R. Meir did not share their concern, and thus required only three judges.]
[Rava disagreed with Ulla's analysis, limiting the dispute to the case in which a court of twenty-three had been convened for a capital charge, which was withdrawn for lack of witnesses, converting it to a monetary case.. The difference between the Sages and R. Meir was concern for the dignity of the court.]
[The gemara will now raise a question about Ulla's interpretation.] They asked [based on the following b'raita]: And the Sages say: If he [the husband] claims money [the difference between the ketubah payment for a virgin versus a non-virgin], a court of three [is required], but if he seeks capital punishment, twenty-three.
This is consistent with Rava [concern for the dignity of the court]; if he claimed money, it was a court of three, and if he initially sought capital punishment, even if the case was later limited to money [e.g., he could not find witnesses to her adultery], it would be a court of twenty-three. But this is inconsistent with Ulla [who holds that a court of twenty-three would be required even if the initial claim was only monetary, lest witnesses appear].
Rava said: I and the lion of the group, namely Rav Hiyya bar Avin, explained: The b'raita is dealing with a case in which the husband brought witnesses to the adultery, and the father brought discrediting witnesses [i.e., witnesses that testify that the first set of witnesses could not have seen what they claimed because they were elsewhere at the time]. If the father comes to collect a monetary penalty from the husband, it is by a court of three. But in a case of capital punishment, a court of twenty-three would be required.
[In the case of a slanderer, the Sages require a court of twenty-three; R. Meir requires only a court of three. Ulla explained that the dispute centered on whether one is concerned that witnesses might appear {and make it a capital offense}. Rabbah [as emended] attributed the dispute to whether one was concerned for the dignity of the court. We now see a third explanation for the dispute.]
Abbaye said: Everyone [the Sages and R. Meir] agrees that we are concerned about gossip [that will attract witnesses to the woman's adultery], and we are concerned with the honor of the first set of judges.
[As far as halakhah is concerned, Abbaye unifies Ullah's approach with that of Rabbah: A court of of twenty-three is convened even when there are no witnesses, in case gossip may induce witnesses to appear, and the full complement remains even after the capital charge against the woman is dismissed and only a monetary claim remains. This ruling, which is accepted by Rambam, contradicts that of Rava, who ruled that if the case is initially a monetary one, three judges suffice.]
[So what is the basis for the dispute between the Sages and R. Meir?] We are dealing with a case in which the witnesses warned her in a non-specific way [i.e., without specifying the mode of execution].
[Rashi: This was ascertained in a hearing before three judges, in which the husband sued for reduction of the marriage contract.]
(R. Meir agrees with) the tanna of the following b'raita: All the other people mentioned in the Torah who are eligible for the death penality [other than one who tempts others into idolatry] are not executed without a court of twenty-three, witnesses and warning, and until they [the witnesses] warn him that he will be liable for judicial execution. R. Yehudah says: Until they warn him of the specific form of execution that would be imposed.
[Thus, the difference between R. Meir and the Sages may simply be whether the warning was explicit enough. R. Meir agreed with R. Yehudah, that the warning had to include the method of execution; since it did not, our mishna's case remains monetary rather than capital, and only three judges are required.]
[A fourth explanation:] Rav Pappa said: We are dealing with the case of a scholarly woman, which parallels the dispute between R. Yosei b. Yehudah and the Sages. For we learned in a b'raita: R. Yosei b. Yehudah said: A scholar does not require warning, because warnings are only given to distinguish between intentional and unintentional acts.
[According to R. Yosei b. Yehudah, the defense of ignorance cannot be made by a scholar, so an improper warning by the witnesses cannot exonerate the defendant. The Sages are presumed by R. Pappa to have adopted this rule whereas R. Meir rejected it.]
[A fifth explanation:] Rav Ashi said: For example [our mishna is discussing a case in which] she was warned about lashes but not the death penalty. [Rashi cites a general halakhic principle that any capital crime for which the transgressor was warned only about lashes is only given the lashes. Therefore, if found guilty, the woman is lashed rather than put to death].
And this is equivalent to the dispute between R. Yishmael and the Sages, as we learned in our mishna: [Offenses punishable by] lashes are judged by three; in the name of R. Yishmael they said twenty-three. [R. Yishmael's rationale will be explored subsequently.]
[The two last examples imply that the Sages follow R. Yosei b. Yehudah and R. Yishmael respectively, whereas R. Meir follows the majority in those two cases.]