Rosh Chodesh ראש חודש
The beginning of the month—the first commandment given to the people as a people: time was put into the hands of a court, which sanctifies the month on the evidence of witnesses.
"This month shall be to you the head of months; it shall be the first month of the year to you." Rashi asks why the Torah, a book of commandments, does not begin with this verse—and so shows how important it is: with it the people's reckoning of time begins.
The procedure was living and human. Witnesses who had seen the new moon came before the court; they were questioned separately; if their testimony agreed, the head of the court proclaimed "Sanctified!" and all the people repeated it. The new month was announced by fires on the mountain tops, and when the Samaritans began to light false fires, by messengers.
Every festival depends on this day: they are counted from the beginning of the month, and that is why power over the calendar was the thing most guarded. When persecution began in the fourth century, Hillel the Second drew up a fixed calculated calendar—the one by which the people live to this day.
On the timeline
Sources
Tanakh
- Exodus 12:1–2 — «this month shall be to you the head of months»
Chazal: Mishnah, Talmud, midrash, Zohar
- Mishnah Rosh Hashanah 2:5–7 — the questioning of witnesses and the proclamation «Sanctified!»
- Mishnah Rosh Hashanah 2:2 — the fires on the mountain tops and the Samaritans' false ones
Rishonim
- Rashi on Genesis 1:1 — why the Torah might have begun with this verse
- Rambam, Mishneh Torah, Sanctification of the New Moon 5:3 — the fixed calendar
Basis: Talmud and midrash.