Shortly before sundown on the 29th of Adar, G-d commanded Moses regarding the mitzvah of sanctifying the crescent new moon and establishing a lunar calendar. This is the first mitzvah the Jews were given as a nation.
Moses had difficulty envisaging the moon's appearance at the exact moment of its monthly rebirth. After the sun set, G-d showed Moses the crescent new moon of the new month of Nissan, showing him the precise dimensions of the moon at the moment the new month is to be consecrated.
For the generations that followed, each new month was ushered in when two witnesses testified before the Sanhedrin (rabbinic supreme court) that they had seen the molad, the new moon. In the 4th century CE, Hillel II foresaw that the Jews would no longer be able to follow a Sanhedrin-based calendar. So Hillel and his rabbinical court established the perpetual calendar which is followed today -- until Moshiach will come and reestablish the Sanhedrin.
Links::
Lunar Time
Rosh Chodesh
The Molad
A few months after its creation, Napoleon's "Sanhedrin" (rabbinical supreme court) was dissolved. The Sanhedrin was created to approve certain religious regulations requested by the French "Assembly of Notables." The regulations were designed to blur the distinction between Jews and non-Jews.
The rulings of this pseudo-Sanhedrin were never adopted by Jewish communities.
Link:: Napoleon Bonoparte
On Simchat Torah we dance with our feet, not with our heads.
We are celebrating the Torah, and the Torah is something we study with our heads. But we dance with our feet, not with our heads.
If we would dance with our heads, each one would dance a different dance, each in a different space, some with friends but not with others, some as lonesome souls.
One head is higher, one is lower, one is here on earth, the other in the clouds or beyond, and some minds know only their own space that no one else can know.
But we dance with our feet, and all our feet are here on the same earth—none higher and none lower. So now we can all dance as one, with one heart, as a single being.
Now there is no loneliness, only joy.