Ramban, in Drasha L'Rosh Hashanah, shows that time had originally been
measured from Tishrei (Rosh Hashanah time). Only when the Torah commanded
to count the months from Nisan, did the Jewish Calendar take shape.
The author of the Flah (Rav Pinchus Halevi Horowitz), writes that the
ancient time mechanisms of antiquity placed the beginning of the day of
twenty-four hours at daybreak. It was only with the Torah that the Jews would
begin counting days at nightfall. (See Panim Yafos). The verse in Vayikra
23:31 delineates the time frame for Yom Kippur: "On the ninth day, in the
evening, from evening to evening, you shall rest." The words "from evening
to evening," teach that the Torah day of twenty four hours extends from night
Rav Moshe Sternbuch (Moadim Uzmanim, part 5, #315) and Rav Yaakov Kamenetsky
(Emes L'yaakov Parshas Bo 12:2) show how this concept fits perfectly into
the verse: "Eat matzos on the fourteenth at night." (Shmos [Exodus] 12:18).
Pesach is the fifteenth of the month -- why does the Torah here state the
"fourteenth at night?" Since they still had the laws of Bnei Noach (the Torah
hadn't yet been given), the night belonged to the previous day. The night
of Pesach actually occurred on the night of the fourteenth (that is, the
night following the fourteenth day). In later years it would be seen as the
night of the fifteenth, because the night would precede the day.
The Problem of Shavuos
In Outline #31, we refered to a famous problem. The festival of Shavuos
occurs on the fiftieth day following Pesach. By tradition, Shavuos celebrates
the receiving of the Torah at Mt. Sinai. However, the two don't seem to
correspond! Everyone agrees that the Torah was given on a Shabbos; Seder
Olam (cited in Tur 430, also see Rivash 96) holds that the Jews left Egypt
on a Thursday. If so, the Torah was given 51 days after Pesach, which does
not correspond to Shavuos at all!
Based on words of the Flah (mentioned above), Chasom Sofer (Toras Moshe
Parshas Bo) explained how the Torah was given on the 51st day after Pesach,
yet is celebrated on Shavuos, the fiftieth day. The Jews were to count forty-nine
days after Pesach, and the fiftieth day would be the receiving of the Torah.
However, a change in the counting system took place during this time. Before
the laws of the Torah were in effect, the night followed the day; when the
Torah would be given, however, the night would precede the day. We have here
a discrepancy of twelve hours.
They started to count on Friday night (which was in the middle of their
pre-Torah day, not the beginning). If we are to count whole days only, fifty
days would not be complete until Friday night, seven weeks later. According
to the new calendar of the Jews, however, it would be seen as having occurred
fifty one days later; Friday night is Shabbos, a different day!
Rav Moshe Sternbuch answers in a similar manner (Moadim Uzmanim, part
5, #315). Also see a beautiful description in Sefer Hatoda'ah (Book of our
Heritage) under "Shavuos." The gist of these answers is that there was a
discrepancy of twelve hours, due to the change in time measurement, which
accounted for the extra day.
Further, in Moadim Uzmanim, an explanation for the custom to stay up all
night, studying Torah on Shavuos, is presented. This night is the period
of transition -- as the time mechanism from antiquity changed, the Jews converted
from Bnei Noach to the Holy Nation. Who would want to sleep through the
Haaros -- insights presented in a novel manner -- are meant to stimulate
provoke, but are by no means conclusive. Readers are encouraged to look
original sources. Since there are many factors that might be taken into
consideration, actual questions regarding Jewish Practice should be addressed
to the appropriate authorities.
Rabbi Yaakov Bernstein PC Kollel 1 Babbin Court Spring Valley,
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