The Hebrew calendar is a ‘lunar’ calendar, meaning it begins on the new Moon, the full moon is mid month and when the moon ends waning the month has ended.
The Gregorian calendar is a ‘solar’ calendar, based on the Sun.
The Hebrew calendar has 7 leap years in 19 years. When they have a leap year they add an entire month. It is always added to be the month before Nisan, when the Biblical year begins (Passover). The leap months are added to keep sync with the Sun (solar) cycle.
This next year that begins September 9, 2010 is Tishri 1, 5771. These are the years counted since the creation of Adam. This year will have 13 months, the last two months are Adar I and Adar II. The Feast of Purim is always the month before Nisan, so this next year Purim will be Adar II.
In 2008, both the solar calendar and lunar calendars had leap years. The solar added the 29th to the month of February and the lunar added Adar II to the end of their year. (FYI, Presidential elections and Summer Olympics are on a leap year- so does that mean we take a giant leap of faith when we go to the polls?) The next solar leap year will be 2012.
The Hebrew Tribe of Issachar was gifted with the complex understanding of the times (I Chronicles 12:32). This is done by an understanding of the heavens lights that rule the day and night. Without knowing the leap year timing, the children of Israel would not be in the correct season to go up for the appointed Feasts of the Lord.
It is interesting to note that the root word of Issachar is Nasa, meaning ‘to lift , to advance, arise, bring forth, carry away, exalt, high, hold up, lofty, raise up“. What a coincidence that our space program, NASA, lifts off into space, keeping us informed with the heavenly signs.
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