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Rosh Hashanah 23


OPINION: The Mishnah describes how the witnesses who saw the new moon were cross examined and interrogated. The Mishnah later (24a) relates that Raban Gamliel kept models of the moon in different shapes and facing different directions in order to show the simple people who came as witnesses samples of how they saw the new moon. These Mishnayos clearly imply that the declaration of the new month was determined solely by authenticating the testimony of witnesses.

RABEINU BACHYE (Parshas Bo 12:2) cites a very interesting opinion in the name of RABEINU CHANANEL, which is also cited in the name of RAV SA'ADYAH GA'ON (see TORAH SHELEIMAH vol. 13, #293, and OTZAR HA'GE'ONIM to Beitzah, p. 3), that Kidush ha'Chodesh actually has nothing to do with witnesses. Rather, it is determined solely by the calculations of the Sod ha'Ibur given to Moshe Rabeinu at Sinai, with which the Beis Din calculates the new month every month. Witnesses did not affect the determination of the new month at all.

Rabeinu Chananel cites a number of proofs for this opinion. First, for the forty years that the Jews sojourned in the Midbar, they were covered and protected by the Ananei ha'Kavod, the Clouds of Glory. If so, it was impossible to see the new moon, and thus it must not have been necessary to see the new moon in order be Mekadesh the Chodesh!

Second, we find that in Shmuel I (20:5) David ha'Melech tells Yonasan that on the next day there will be a Rosh Chodesh meal, and on the following day there was a meal for the second day of Rosh Chodesh. How did they know that the next day would be Rosh Chodesh if witnesses had not yet come? And if it was Rosh Chodesh, why should there be a second day of Rosh Chodesh? It must be that they worked only with calculations. (Both days were considered Rosh Chodesh, since the calculations showed that the new month started towards the end of the thirtieth day, as the Rambam writes, Hilchos Kidush ha'Chodesh 8:4).)

Third, the Mishnah (25a) states that Raban Gamliel was Mekadesh the Chodesh even when the testimony of the witnesses was physically impossible to have been correct. (See Insights to Daf 25.)

Fourth, the Mishnah (25b) states that when all of the Jewish people see the new moon but there is not enough time to be Mekadesh the new month before nightfall, the Beis Din is Mekadesh the next day instead. If the new month depends on the testimony of witnesses, why does Beis Din not declare on the next day that the previous day was Rosh Chodesh (retroactively)? It must be that it has nothing to do with seeing the new moon, but rather it depends solely on the calculations.

However, why do all of the Mishnayos discuss witnesses in the first place if Kidush ha'Chodesh has nothing to do with witnesses, but with the calculations? He answers that the Tzedukim did not accept the calculations of Beis Din. They did not believe in the Mesorah of Sod ha'Ibur, and they claimed that the month is determined by when the moon actually appears. Based on mathematical calculations alone, they claimed that Beis Din could not possibly know when exactly the new moon will appear every month. They only accepted the testimony of witnesses who saw the new moon. Therefore, in order to prove the Tzedukim wrong, the Beis Din said that they would Mekadesh the Chodesh based on the testimony of witnesses, which would then show that their mathematical calculations are always correct. Hence, it is a Mitzvah d'Rabanan to be Mekadesh the Chodesh based on testimony of witnesses. This is why Raban Gamliel had models of the moon -- it was in order to discredit the Tzedukim ("Hedyotos"). Every month on the day before the new moon appeared, he would show them where the new moon would be seen *the next day*. When witnesses arrived in court the following day to testify that the moon was actually seen where the court expected it, those who attended proclaimed in unison "Mekudash, Mekudash!" -- the calculation of Beis Din was correct!

Eventually the Tzedukim were won over, but the Beis Din kept the practice of accepting witnesses of the new moon in order to remember how the Chachamim overcame the Tzedukim.

According to this unique opinion that the new month depends solely on calculations and not on witnesses, why are there two days of Yom Tov outside of Eretz Yisrael (or two days of Rosh Hashanah even in Eretz Yisrael)? The Ge'onim (OTZAR HA'GE'ONIM Beitzah p. 3) answered that keeping two days of Yom Tov outside of Israel is a Halachah l'Moshe mi'Sinai!

(b) The RAMBAM (Perush ha'Mishnayos) strongly rejects this explanation, for it contradicts many explicit statements in the Gemara. It is obvious that they were Mekadesh the Chodesh based on witnesses, and only when there were no witnesses did they do it based on calculations. The Rambam suggests that perhaps Rabeinu Sa'adyah wrote this opinion because of the Karaites in his time who were pestering him, saying that Kidush ha'Chodesh based on calculations is unreliable. In response, Rav Sa'adyah said that not only is Kidush ha'Chodesh based on calculations completely accurate, but Kidush based on witnesses is not even mid'Oraisa.

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