On the 6th Sivan of the year 2448 from creation (1313 BCE), seven weeks after the Exodus, G-d revealed Himself on Mount Sinai. The entire people of Israel (600,000 heads of households and their families), as well as the souls of all future generations of Jews, heard G-d declare the first two of the Ten Commandments and witnessed G-d's communication of the other eight through Moses. Following the revelation, Moses ascended the mountain for 40 days, to receive the remainder of the Torah from G-d.
At Sinai, G-d rescinded the "decree" and "divide" (gezeirah) that had been in force since the 2nd day of creation separating the spiritual and the physical into two hermetic worlds; from this point on, "the higher realms could descend into the lower realms, and the lower could ascend to the higher." Thus was born the "mitzvah" -- a physical deed that, by virtue of the fact that it is commanded by G-d, brings G-dliness into the physical world.
During the first crusade (see "Today in Jewish History" for Iyar 8), the Jews of Cologne, Germany chose to be killed rather than convert to Christianity. This was the case, during the first crusades, for many of the Jews who were given the choice between being killed or being baptized. Most of those who converted continued to practice Judaism in secrecy and, one year later, were permitted by Henry IV to openly return to Judaism.
In 1734, Rabbi Israel Baal Shem Tov ("BeSHT", 1698-1760), who up until that time had lived as a hidden tzaddik, began to publicly disseminate his teachings. While adding nothing "new" to Judaism, he re-emphasized truths and doctrines that had been buried under the hardships of exile: the immense love that G-d has for every Jew, the cosmic significance of every mitzvah a person performs, the divine meaningfulness that resides in every blade of grass, in every event, and in every thought in the universe. He spoke to the downtrodden masses and to the aloof scholars, giving meaning to their existence, and thus joy, and thus life. Many disciples came to imbibe the "inner soul" of Torah from him, and the new movement came to be known as "Chassidism."
Rabbi Israel passed away on the 6th of Sivan of 1760, and was succeeded (one year later, on the first anniversary of his passing) by his disciple, Rabbi DovBer of Mezeritch.
Links: Rabbi Israel Baal Shem Tov
The Torah reading for the 1st day of Shavuot is from Exodus 19-20, which recounts the giving of the Torah at Mount Sinai (see "Today in Jewish History") and includes the "Ten Commandments" proclaimed at Sinai that encapsulate the entire Torah.
Links:
The Shavuot Torah Readings
About the Ten Commandments
The Lubavitcher Rebbe urged that all children -- including infants --should be brought to the synagogue on the 1st day of Shavuot to hear the reading of the Ten Commandments in re-enactment of the Giving of the Torah at Sinai. Our sages relate that when G-d came to give the Torah to the people of Israel, He asked for a guarantee that that they will not forsake it. "The heaven and the earth shall be our guarantors," said the Jews, but G-d replied that "they will not last forever." "Our fathers will guarantee it," said the people, but G-d said that "they are busy." It was only when we promised that "our children will guarantee it" that G-d agreed, "These are excellent guarantors."
Link: Our Children, Our Selves
It is the custom in many communities to read the biblical Book of Ruth, which tells the story of Ruth, a Moabite princess--and ancestress of King David--who converted to Judaism.
Links:
Text of Book of Ruth and its connection to Shavuot
How Does One Convert to Judaism?
It is customary to eat dairy foods on Shavuot. Traditional Shavuot dairy foods include cheesecake and blintzes.
Visit our Shavuot megasite
Tomorrow is Yizkor. Those who light a candle should so this afternoon from a pre-existing flame before lighting Shabbat/holiday candles (or have lit a long-lasting candle before the onset of the holiday).
Take these words of Mine to your hearts and to your souls…teach them to your children so that this will be what they speak about, when you are sitting at home, walking on your way, lying down to rest, and arising from your sleep. (Deuteronomy 11:18-19)
The simple meaning of this instruction is as follows:
You must teach your children Torah.
Not as a burden, but as a love; so that they will cherish Torah wisdom, share it, and speak about it at every time of day, in every circumstance. Until it becomes the defining activity of their lives.
And to accomplish this, you too must be engaged, heart and soul, in your children's education the entire day.
Not only at home, when you are in your own space, but even when you're off at work or in other circumstances you do not control, this is what should preoccupy your mind.
So that when you lie down to rest after a long, hard day, the concern won't go away.
And when you awaken refreshed in the morning, your first thought will be, "What's happening with my children's education?"
This is why there are Jews today, how this miracle occurred: Because there were Jewish parents who focused their entire lives on the Torah education of their children.