Does a Jewish Year Really Have 13 Months?

I have a question. Are there thirteen months in a Jewish year?
What does the year of double Adar mean? What is its significance and what spiritual implications are there?

I appreciate you being there.

Mariam S.

Dear Mariam,

The answer to your question is both yes and no. Most years, the Jewish year consists of twelve months. Seven years in every nineteen years the month of Adar, which usually straddles February and March, is repeated. Those years contain thirteen months, including an Adar One and an Adar Two. While the Gregorian calendar with which we are most familiar adds a leap day every four years, the Jewish calendar adds a leap month.

What is going on? We actually go quite into depth on the calendar in episode 10 of our Scrolling through Scripture Genesis, Unit One course. You see, the solar year is about 365 days long while the lunar year, made up of 12 lunar months, comes out at about 355 days long. It follows that the lunar date falls behind the solar date by about 30 days every three years. Thus approximately every 3 years (actually 7 in every 19) we add the extra month of Adar, approximately another 30 days bringing the solar and lunar years back into synchronization.

Like so many amazing concepts, when we are accustomed to something we stop realizing how amazing it is. We grow up with the Base 10 decimal system, for example, and don’t stop to ask ourselves how and why that is the basis for math. We expect things to fall down, but it needed Isaac Newton to stop and ask why that happens and what laws govern that action. Similarly, we accept the divisions of time and the calendar without gaping in wonder every time we jot down an appointment.

Ancient Jewish wisdom on Genesis 1:14 lays out the idea that the “lights” discussed in that verse help us navigate both through space and time. While the Gregorian calendar is based on the solar system and the Moslem calendar is based on the lunar cycle (this is why Ramadan moves throughout the year), the Jewish calendar is based on both the solar and lunar cycles.

In a debate between mathematicians in the late 1500s or early 1600s, French mathematician Joseph Justus Scaliger claimed that the Hebrew calendar is the most perfect creation of man. Of course, he is inaccurate as it is the creation of God, not of man. Nonetheless, the Hebrew calendar does continue to work as it has for millennia, without needing any tweaking.

What are the implications of Adar being the month chosen for doubling? There are too many to discuss here. We will just mention one intriguing fact. The zodiac sign associated with Adar is Pisces. (Yes, the zodiac signs have significance even if that importance is not related at all to today’s horoscopes. We discuss more of that in our audio CD, Day for Atonement.) The pictogram associated with that sign is not one fish, but two and the word fish can be both a singular and a plural. In fact, the only zodiac sign that is a plural is ‘fish’ which is associated with the only month that can be two. (Gemini is one set of twins.) Intriguing indeed.

We appreciate your learning alongside us,

Rabbi Daniel and Susan Lapin

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We are proud to share this wonderful new course by Rabbi Daniel Lapin:

The Book of Ruth: Chorus of Connection

One of the best-known and most beloved books of Scripture, the book of Ruth is a compelling story of love, family and redemption.

Yet, it is so much more. It is a blueprint for our times, describing how to repair a splintered society and how individuals can best connect and flourish.

  • What similar ideas highlight both a good marriage and a good government?
  • What is the connection between fertility and prosperity?
  • Can Seduction and Sanctity co-exist?
  • Can societies in decline reverse course? How?
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