(a) The Ritva gives a different answer and writes that one is forced to say that the Tana of the Mishnah certainly was not accurate when he used the word "Bilvad". In fact what the Tana meant to say is that a set of witnesses is only killed when it came to be "Mazim" ( i.e. prove that the witnesses could not have seen the event that they claimed to have witnesssed) just one set of "Eidim."

The set of witnesses that are sitting in front of us, who they are in this case trying to be Mazim, is therefore termed the "Rishonah" - "first". If this set is "Bilvad" - i.e. on its own without any other sets - then its witnesses would be killed. The Ritva writes that it is impossible to explain the Mishnah any other way.

(b) The Tosfos Yom Tov gives a different answer according to the Rambam's explanation in the Pirush ha'Mishnayos. The Rambam cites R. Yehudah's statement that only the first "Kas" is killed and adds on that one does not listen to any groups of Eidim that subsequently come. The Bartenura elaborates somewhat that R. Yehudah maintains that once the first "Kas" has been proven to be fakers we will never accept any other sets of Eidim who come to give the same testimony as the discredited first set. (Even if Eidim who gave the same Eidus as the first set would afterwards also be discredited, nevertheless the second lot would not be killed because since we do not accept their testimony to kill the so-called murderers, it follows that we can also not kill them for their false intentions.) We assume that anyone who subsequently comes to give testimony like the killed false witnesses, are also liars (see Tosfos Yom Tov).

The Tosfos Yom Tov now asserts that when R. Yehudah says that the final Kas of Eidim who try to be Mazim the other 100 sets is "Istasit", he is making this statement only according to the Rambam's opinion, whereas he himself does not need to say Istasit. This means that R. Yehudah retorted to the Rabanan that according to you that you are prepared to accept the second Kas, and do not say that anyone who testifies like the convicted Eidim are automatically liars, you should at least agree to me that one should not kill all the 100 disredited sets of Eidim. However R. Yehudah makes it clear that he himself maintains that only the first Kas is killed and no more.

The Tosfos Yom Tov now asks what forced the Rambam into saying that R. Yehudah's statement was only relating to the Rabanan's position, but not to his own. He answers that according to the Rambam's explanation the words of R. Yehudah in the Mishnah now fit in well and the question that the Gemara asks as a "Kashya" can be answered. When R. Yehudah said in the Mishnah "Only the first Kas is killed", this is consistent with the way the Rambam explained his position: because the first Kas was killed, one cannot therefore kill any other sets of witnesses, simply because we do not accept any other witnesses after the death of the first set. So R. Yehudah has to say that the first set was killed, because otherwise we could have continued to receive Eidim.

Now the Tosfos Yom Tov introduces a new element and asserts that when the Gemara remained with an unanswered question on the Mishnah this was because the Gemara was using different reasoning than that mentioned by the Rambam. The reasoning the Gemara follows at this stage is that given by Rashi 5a DH Istatis that this last Kas is trying to disqualify anyone giving this Eidus.

In short, the Gemara's unanswered question can in fact be answered if we understand that the reasoning of R. Yehudah is that once one Kas has been killed we must stop accepting any other witnesses. However the Gemara itself had no answer for this question because the Gemara understood that one Kas of Mezimim can only kill one other Kas.

A Gut Chodesh

Dovid Bloom