1MISHNA: In a case where there were two witnesses observing an individual violating a capital transgression from this window in a house, and two observing him from that window in a house, and one person was forewarning the transgressor in the middle between the two sets of witnesses, the halakha depends on the circumstances. In a situation where some of the witnesses observing from the two windows see each other, the testimony of all these witnesses constitutes one testimony, but if they do not see each other, the testimony of these witnesses constitutes two independent testimonies. Therefore, as two independent sets of witnesses, if one of the sets was found to be a set of conspiring witnesses, while the testimony of the other set remained valid, both he, the one accused of violating the capital transgression, and they, the conspiring witnesses, are executed, and the second set, whose testimony remained valid, is exempt.
2Rabbi Yosei says: Transgressors are never executed unless his two witnesses are the ones forewarning him, as it is stated: “At the mouth of two witnesses… he who is to be put to death shall die” (Deuteronomy 17:6), from which it is derived that it is from the mouths of the two witnesses that the accused must be forewarned, and forewarning issued by someone else is insufficient. Alternatively, from the phrase “at the mouth of two witnesses” one derives that the judges must hear the testimony directly from the witnesses, and the Sanhedrin will not hear testimony from the mouth of an interpreter.
3GEMARA: Rav Zutra bar Tuvya says that Rav says: From where is it derived with regard to disjointed testimony, in which each of the witnesses saw the incident independent of the other, that it is not valid? It is derived from a verse, as it is stated: “He shall not die at the mouth of one witness” (Deuteronomy 17:6). The exposition is as follows: What is the meaning of “one witness”? If we say that it means one witness literally, we learn it from the first portion of the verse: “At the mouth of two witnesses,” indicating that the testimony of fewer than two witnesses is not valid. Rather, what is the meaning of “one witness”? It means that the accused is not executed based on the testimony of people who witnessed an incident with one witness here and one witness elsewhere.
4The Gemara notes: This is also taught in a baraita : It is written: “He shall not die at the mouth of one witness,” from which it is derived to include the halakha that in the case of two witnesses who observe an individual violating a capital transgression, one from this window and one from that window, and they do not see each other, that they do not join to constitute a set of witnesses. Moreover, even if they witnessed the same transgression from the same perspective, watching the incident not at the same time but one after the other in one window, they do not join to constitute a set of witnesses.
5Rav Pappa said to Abaye: Why is it necessary to mention both cases? Now if in the case where one witness views the incident from this window and one witness views the incident from that window, where this witness sees the entire incident and that witness sees the entire incident, you say that they do not join to testify together as two witnesses, if they see the incident one after the other, where this witness sees half the incident and that witness sees half the incident, is it necessary to say that the witnesses do not join together? Abaye said to him: It is necessary to state this halakha only with regard to a case where they witnessed one who engages in intercourse with a forbidden relative, which is a continuing act, and each of the witnesses saw sufficient behavior to render the transgressor liable. The tanna of the baraita teaches that even in that case, they do not join to constitute a set of witnesses.
6Apropos witnesses joining to constitute a set of witnesses, Rava says: Even if the witness in either window is unable to see the witness in the other window, if the witness in each window sees the one who is forewarning the accused, or if the one who is forewarning the accused could see the two disjointed witnesses, they join to constitute a set of witnesses. Rava says: The one forewarning the accused of whom the Sages spoke need not be a third witness, but even if the victim forewarns the murderer from his own mouth, and even if the forewarning emerged from the mouth of a demon, meaning the source of the forewarning is unknown, the forewarning is legitimate.
7Rav Naḥman says: Disjointed testimony of two witnesses, each of whom observed an incident independent of the other, is valid in cases of monetary law, as it is written: “He shall not die at the mouth of one witness” (Deuteronomy 17:6). This indicates that it is only with regard to cases of capital law that disjointed testimony is not valid, but with regard to cases of monetary law that testimony is valid.
8Rav Zutra objects to this: But if that is so, and disjointed testimony is effective in certain cases, in cases of capital law disjointed testimony should spare the accused from execution. Since one must exploit every avenue possible to prevent executions, in a case where some of the disjointed witnesses were rendered conspiring witnesses, the entire testimony should be voided on their account. Why, then, did we learn in the mishna that if one set witnessed the capital transgression from one window and one set from the other window, and one set was found to be a set of conspiring witnesses, he, the accused, and they, the conspiring witnesses, are executed? The Gemara comments: Indeed, that is difficult according to Rav Naḥman.
9§ The mishna teaches that Rabbi Yosei says: Perpetrators are never executed unless his two witnesses are the ones forewarning him. Rav Pappa said to Abaye: And is Rabbi Yosei of the opinion that this line of reasoning is correct, and forewarning by the witnesses is indispensable? But didn’t we learn in a mishna (9b): Rabbi Yosei says: An enemy who commits murder cannot claim that he killed the victim unwittingly. Rather, he is executed even if there was no forewarning, due to the fact that his halakhic status is like that of one who is cautioned and forewarned. Apparently, Rabbi Yosei does not always require that there be forewarning.
10Abaye said to him: That statement in the mishna you cited that is attributed to Rabbi Yosei is actually the opinion of Rabbi Yosei bar Yehuda, as it is taught in a baraita : Rabbi Yosei bar Yehuda says: A ḥaver does not require forewarning, as forewarning was instituted only to distinguish between one who commits a transgression unwittingly and one who does so intentionally. A ḥaver , who is a Torah scholar, does not require forewarning to distinguish between them. Rabbi Yosei ben Ḥalafta, whose opinion is cited in the mishna here, is of the opinion that forewarning is a necessary prerequisite to executing someone who is judged liable, and that forewarning must be issued by the witnesses.
11§ The mishna teaches: Alternatively, from the phrase in the verse “at the mouth of two witnesses” one derives that the Sanhedrin will not hear testimony from the mouth of an interpreter. The Gemara relates: There were certain people who spoke a foreign language who came before Rava for judgment. Rava installed an interpreter between them and heard the testimony through the interpreter. The Gemara asks: And how did he do so? But didn’t we learn in the mishna that the Sanhedrin will not hear testimony from the mouth of an interpreter? The Gemara answers: Rava knew what they were saying, as he understood their language, but he did not know how to respond to them in their language. He posed questions through the interpreter but understood the answers on his own, as required by the mishna.