Talmud for Ketubot 11:2
אַלְמָנָה, בֵּין מִן הָאֵרוּסִין בֵּין מִן הַנִּשּׂוּאִין, מוֹכֶרֶת שֶׁלֹּא בְּבֵית דִּין. רַבִּי שִׁמְעוֹן אוֹמֵר, מִן הַנִּשּׂוּאִין, מוֹכֶרֶת שֶׁלֹּא בְּבֵית דִּין. מִן הָאֵרוּסִין, לֹא תִמְכֹּר אֶלָּא בְּבֵית דִּין, מִפְּנֵי שֶׁאֵין לָהּ מְזוֹנוֹת, וְכָל שֶׁאֵין לָהּ מְזוֹנוֹת, לֹא תִמְכֹּר אֶלָּא בְּבֵית דִּין:
A widow, both from betrothal [in which instance she is not fed (from the property of the inheritance) and she sells her kethubah], both from marriage [in which instance she sells (from the property of the inheritance) for food], sells not before beth-din. [That is, not before a beth-din of experts. But in any event, she must sell before three who are expert in the assessment of land.] R. Shimon says: From marriage, [in which instance she sells (property) for food], she sells not before beth-din, [for she cannot sit and suffer until she finds a beth-din, but] from betrothal [where her sale is only for (collection of) the kethubah], she sells only before beth-din. [The halachah is not in accordance with R. Shimon.]
Jerusalem Talmud Makkot
Rebbi Simeon says, since two are executed only if both are plotters, so three are executed only if all three are plotters. And from where even a hundred? The verse says “witnesses”42The repetition, two witnesses or three witnesses, when it could have been “two or three witnesses”, implies that any number of witnesses have the same status as do two..
Rebbi Aqiba says, the third is only mentioned to punish him harshly and to identify his judgment with that of the others. If the verse in this way punished the accessory of criminals like criminals43Since the third witness is not essential for proof in court., so much more it will reward the accessory to one who keeps the commandments as one who keeps the commandments.
Since the testimony of two [witnesses] is invalid if one of them is found to be a relative or a disqualified person51If one witness is disqualified by the rules of Mishnah Sanhedrin either 3:6 or 3:7, there is only one testimony, insufficient by biblical standards., the same holds for three if one of them is found to be a relative or a disqualified person. From where even for a hundred? The verse says42The repetition, two witnesses or three witnesses, when it could have been “two or three witnesses”, implies that any number of witnesses have the same status as do two., witnesses.
Rebbi Yose said, when has this been said? In criminal trials, but in civil trials the testimony should be upheld by the remaining [witnesses]52Since Deut. 19:19 is formulated for criminal trials, the argument that any number of witnesses have the same status as two witnesses is not necessarily true for civil trials. In money matters, any two qualified witnesses can testify. For example, it is admissible that marriage contracts be signed first by two qualified witnesses and after them by any number of family members of both sides (cf. Gittin 8:12, Note 105).. Rebbi says, both in criminal and in civil trials, if they warned them53If in a criminal case a disqualified person or two related persons both warned the perpetrator not to engage in criminal behavior, their action makes them witnesses and all witnesses have to be disqualified under the argument of Mishnah 12. But if they were eye witnesses but not those who delivered the warning, they are not forced to testify; the trial may proceed without them.. But if they did not warn them, what should two brothers do who were eye-witnesses to a murder?