As we begin our study of Leviticus 23 and the feasts God directed the Israelites to celebrate each year, it is important to note that the Jewish calendar differs from the one most countries of the world use today. Unlike our Gregorian calendar that calculates a year by 365 (or 366) rotations around the sun, the Jewish calendar follows the cycles of the moon. However, its 29- and 30-day months aren’t enough to keep up with the solar year, so an extra month is added to this lunisolar Jewish calendar seven times in a 19-year cycle. We are currently in that added month, which is inserted between the Jewish months of Adar and and Nisan. Here’s how the calendars compare and where the Jewish months are mentioned by name in the Old Testament:
