“Have you ever wondered how the Jewish calendar works and how it came about?
The solar orbit consists of 365 ¼ days. The difference between the 12 lunar months and the solar year is almost 12 days.
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In order to balance the solar and lunar cycles, the Sanhedrin periodically inserted an extra month into the year creating the… leap year.
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Hillel the 2nd, the last leader of the Sanhedrin… established a fixed calendar before the Sanhedrin was disbanded [by the Romans].
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Throughout the centuries, the calendar has been one of the backbones of Jewish unity, as it has ensured that Jews the world over celebrate the Jewish holiday’s on the very same day.”