- If an עד זומם is disqualified למפרע or מכאן ולהבא
Amoraim disagree when a witness who was found a זומם is disqualified. Abaye says: למפרע הוא נפסל – he is disqualified retroactively from the moment of testimony (and any subsequent testimonies are invalid), מעידנא דאסהיד רשע הוא – because from the moment he testified, he became a רשע, and the Torah disqualifies a רשע’s testimony. Rava says: מיכן ולהבא הוא נפסל – He is only disqualified from now onward, עד זומם חידוש הוא – because the discrediting of an עד זומם is a novelty. מאי חזית דסמכת אהני– What reason do you see to rely on these second witnesses discrediting the first? סמוך אהני – Rely on these first witnesses who testified they were there! אין לך בו אלא משעת חידושו ואילך– Since it is a novelty, you can only apply it from the time of the novelty and onward, i.e., from the time of the discrediting testimony. Alternatively, Rava holds that although Biblically, an עד זומם is disqualified retroactively, the Rabbis enacted not to disqualify his previous testimonies, משום פסידא דלקוחות – because of the loss of purchasers who used him as a witness in the interim. The Gemara provides practical differences between the explanations. The halachah follows Abaye against Rava and is the "ע" of the "יעל קגם" list of such instances.
- Is מומר אוכל נבילות להכעיס disqualified?
The Gemara states: מומר אוכל נבילות לתיאבון – a renegade who eats meat without shechitah for desire (i.e., because of hunger, where kosher meat is unavailable or more expensive), דברי הכל פסול – all agree he is disqualified from testifying. Since he is willing to sin for financial reasons (i.e., cheaper meat), he might accept money to testify falsely. Amoraim debate the status of one who eats neveilah להכעיס – in defiance of the Torah, even where kosher meat is available. Abaye says he is פסול, because he is a רשע, and the Torah says: אל תשת רשע עד – do not place a wicked person as a witness. Rava says he is כשר, because רשע דחמס בעינן – we require him to be wicked regarding theft to be disqualified (based on the end of the passuk, "להיות עד חמס" – to be a thieving witness). The Gemara discusses how this machlokes relates to a machlokes Tannaim about an עד זומם, whom Rebbe Meir disqualifies for all testimonies, including דיני נפשות, but Rebbe Yose says that if he only testified falsely regarding דיני ממונות, he is not disqualified for the more serious testimony of דיני נפשות.
The halachah follows Abaye, and is the "מ" of "יעל קגם".
- Relatives who are disqualified
The next Mishnah lists the relatives who are disqualified from testifying or judging him: a brother, a father’s brother, a mother’s brother, a sister’s husband, a father’s sister’s husband, a mother’s sister’s husband, a mother’s husband, his father-in-law, and his brother-in-law (his wife’s sister’s husband). For this list, הן ובניהן וחתניהן – they, their sons, and their sons-in-law are all disqualified. וחורגו לבדו – And a stepson alone is disqualified, but not his son or son-in-law. Rebbe Yose says this reflects Rebbe Akiva’s Mishnah, but an earlier version of the Mishnah only disqualified his uncle, his uncle’s son, וכל הראוי ליורשו – and anyone eligible to inherit him. Rebbe Yehudah disqualifies האוהב והשונא – a close friend and an enemy from testifying, which he defines, but the Chochomim said: לא נחשדו ישראל על כך – people of Yisroel are not suspected about [testifying falsely out of love or hatred]. A Baraisa darshens the passuk "לא יומתו אבות על בנים" – fathers shall not be killed because of [their] sons, etc. to mean that fathers are not killed בעדות בנים – based on [their] sons’ testimony, and sons are not killed based on their fathers’ testimony.