The Shavuot holiday is an acknowledgement of the greatest day in human history. The entire Jewish nation heard G-d speak on Mount Sinai, as they were given the Torah. This was the beginning of Judaism for now there was a Torah that would be followed.
It is essential that we also accept that both the Written Law and the Oral Law were given at Sinai. The Oral Law was passed on from generation to generation. It was first explained by Moshe Rabbeinu, himself, in the great Yeshiva of the desert.
The Rambam, in his introduction to Mishna Torah, makes a fascinating point. From the time of Moshe Rabbeinu, until Rabbi Yehuda Hanassi in the year 200 CE, not one book of the Oral Law was put into writing. This covers a span of around 1500 years!
It was only when the realization of a possible long exile set in, that Rabbi Yehuda Hanassi, took upon himself to organize the centuries of oral teaching into the Mishna.
The Rambam further pointed out that there were many instances in our history, where conditions for the Jewish people were very bad, and Torah knowledge suffered.
Miraculously, great Torah scholars emerged to make this knowledge more accessible to the masses. Eventually, the Jerusalem and Babylonian Talmud emerged. Later, during the period of the Geonim, other leaders managed to lead the people. The Rambam’s own contribution was huge, as was that of Rashi.
There is a quote from Rav Yakov Emden that says that a greater miracle than the splitting of the Red Sea, was that Judaism survived throughout the generations.
It was only because of the strict adherence to Torah study, that kept us alive. Thankfully, today in Israel, there is more Torah study going on than at any time in our history.
We show our appreciation of this precious gift of the Torah by studying all night on Shavuot. We must never take this gift for granted.