Jewish vs Gregorian: the differences between the calendars
The Jewish calendar is a complex and important “tool” in Judaism: spiritual life of a religious man is impossible without it. The Jews, regardless of their place of residence, use only it for religious purposes: all holiday/memorable dates and weekly cycles of Torah reading are determined according to this calendar.
In Israel it is official and used together with the Gregorian calendar. The simplicity of the latter made it universally accepted all over the world; however, it is quite difficult to grasp the Jewish calendar. But this makes learning the principles of its arrangement even more interesting – you will understand why it doesn’t coincide with the Gregorian one!
The difficulties start form the very history of its emergence. Nobody knows for sure, but it is accepted officially that the contemporary calendar of Jews was set in year 359 by the head of Supreme religious court (Synedrion, or Sanhedrin) Hillel II.
The system of the Jewish calendar
The rules of its arrangement are complicated owing to the fact that it is both lunar and solar – cycles of both celestial bodies are used. The main rule is that a year coincides with the natural/tropical year, and a month – with the synodical month.
The major difficulty of determination of the Jewish calendar is connected with astronomy: a solar cycle takes 365 days, a lunar one – a little bit more than 29 days and a half (12:43 – h/min). It is impossible to divide the year into 12 equal months. Moreover, there is even an additional 13th month in a leap year, and the number of days in it can be 29 or 30 days (it depends).
In the Gregorian version it was possible to divide a year into 12 months thanks to the “rounding”: it coincides with the lunar cycle just roughly. Ancient Jews have solved this problem in a “Macedonian” style: the notion of “month” as 1/12 is absent at all.
After conquering Phrygia, Alexander the Great found a legendary wagon with the most complicated knot on the yoke in its capital; according to the legend, the one who is able to untie it becomes the ruler of the whole Asia. Without bothering himself, the great commander just split the knot with his sword. And he did conquer Asia after that!
Doesn’t it resemble something to you, the children of Israel?
The difference between the Jewish and Gregorian calendars
A principal difference between the calendars: the Jewish one is non-periodical. One cycle of the Gregorian calendar equals 400 years, the system of the Jewish calendar knows only one period: a 13th month is added to the year seven times during 19 years. As for the rest, there is no periodicity of the dates’ repeating after some sequence of years. To determine the chronology, mathematical calculations and astronomical observations are used.
One more difference – the year begins on a definite day on the week (not Wednesday, Friday or Sunday). The system of Jewish calendar is based on the fact that the first new moon [in the history] occurred on the 7th of October 3761 B.C. Even its time is calculated: 5 hours and 204 parts in the afternoon (a Jewish hour for the calculations = 1080 parts, 1 part = instant).
The main differences that explain why the calendars don’t coincide:
|Days in a month||29/30||29(28)/30/31|
|Start of the month||only on the day of new moon||Every 1st day|
|Start of the year (2017)||September 21||January 1|
|Length of the year (days)||353/354/355/383/384/385||365/366|
Why a Jew needs this calendar
With the help of it you know:
- the dates of Jewish holidays (they are changing constantly);
- when the fasting is to be started and ended;
- on which days the holidays of the State of Israel are falling;
- which Torah portion is read on a definite week;
- when the birthdays are to celebrate and the memory of the dead is to be honored.
The Jewish calendar systematizes and puts in order the spiritual life of every Jew.
You can view all dates of the Jewish calendar here.