Hebrew Calendar: Understanding the Hebrew Calendar

Shalom, everyone! The ancient Bnei Yisrael used two calendar systems to keep time: A civil calendar for day-to-day civil business which began its year in the Fall; and an ecclesiastical calendar for the mo’edim and the reign of kings which began its year in the Spring. Both calendars were lunisolar, using the lunar phases to mark the beginning of months, and intercalation to add the necessary days to make sure that a year lasted 365 solar days thereby assuring that none of the mo’edim were celebrated out of season.

Throughout history, the Bnei Yisrael lived under different calendar systems. While as a tribal family in the Land of Canaan prior to going down to Egypt, the Bnei Yisrael used the same lunisolar calendar system as their Canaanite and Phoenician neighbors. They also spoke the same language, the Canaanite-Phoenician dialect, and even celebrated the same agricultural feasts. During their time in Egypt, the Bnei Yisrael lived under the Egyptian solar calendar. In Exodus 12:1-2The Creator, however, commanded the Bnei Yisrael to create an ecclesiastical calendar for the mo’edim even before their Exodus from Egypt. This calendar was to begin its year in the Spring, six months earlier than the civil year which began in the Fall.  The ecclesiastical calendar was used by the priests to determine the dates for the mo’edim when all Bnei Yisrael were to stop their creative work (melakhah), gather and have holy convocations before The Creator. Though based on the lunar phases, the ecclesiastical calendar is also a lunisolar calendar, with intercalary days added to keep the calendar in sync with a complete solar calendar year.

The Months of the Hebrew Calendar and Mo’edim

The following is a list of the lunar months on the ancient ecclesiastical Hebrew calendar and their respective mo’edim or special event. The appearance of the new moon (first visible crescent) marked the beginning of the month (Rosh Chodesh). Approximately 15 days later, the appearance of the full moon (Keseh) was celebrated with a festival and treated as a day of rest. Also note that the three pilgrimage festivals, Chag HaMatzot, Shavuot and Sukkot were always celebrated on or near the occurrence of a full moon. This ancient calendar was a lunisolar calendar. We have included the ancient Canaanite-Phoenician names for each of the calendar months that would have been known to and used by the pre-exilic Israelites. Also included are the corresponding Akkadian-Babylonian names which the returning post-exilic Judeans adopted for the calendar months after the Babylonian Exile:

Ecclesiastical Month # Canaanite-Phoenician Month Names Civil Month # Akkadian-Babylonian Month Names Season Corresponding Gregorian Months
1  Aviv1 7  Nisan Spring Mar- Apr
2  Ziv2 8  Iyyar Spring Apr – May
3  Mattan3 9  Sivan Spring May – Jun
4  Zabah 10  Tamuz Summer Jun – Jul
5  Karar 11  Av Summer Jul – Aug
6  Tsahim 12  Elul Summer Aug – Sep
7  Ethanim4 1  Tishrei Fall Sep – Oct
8  Bul 2  Cheshvan Fall Oct – Nov
9  Marpa’im 3  Kislev Fall Nov – Dec
 10  Pagrim 4  Tevet Winter Dec – Jan
11  Pe’ulot 5  Shevat Winter Jan – Feb
12  Hayir I 6  Adar I Winter Feb – Mar
13  Hayir II5 Intercalary  Adar II Winter-Spring Mar – Apr

1 Aviv (Nisan): Start of the year for mo’edim; regnal year number increments by 1; Pesach; Chag HaMatzot; counting of the Omer
2 Ziv (Iyyar): Counting of the omer; Pesach Sheni.
3 Mattan (Sivan): Counting of the Omer; Shavuot
4 Ethanim (Tishrei): Start of the civil year; Civil year number increments by 1; Yom Teruah; Yom HaKippurim; Sukkot; Shemini Atzeret.
5 Hayir II (AdarII): Intercalary month, only counted in leap years.

Calculating the Dates for Mo’edim

There are two turns of the year. The first turn of the year occurs in the Spring, the second turn of the year occurs in the FallSpring usually begins with the arrival of the Vernal (SpringEquinox on approximately March 19-21 of each year, however, sometimes this may vary. Fall usually begins with the arrival of the Autumnal (Fall) Equinox on approximately September 22-23 of each year, however, sometimes this may also vary. The civil Hebrew calendar begins with the turn of the year that occurs in the Fall. The ecclesiastical Hebrew calendar begins with the turn of the year that occurs in the Spring. Because the ecclesiastical year begins in the Spring, the First Month, Aviv (Nisan), usually begins with the first new moon sighted after the arrival of the Vernal Equinox. There are other factors to consider, however, before declaring a new year for mo’edim on the ecclesiastical calendar. Please note that these factors are relevant in the Northern Hemisphere:

  • Arrival of the “latter” rains: These rains occur in the Spring, and are necessary for the ripening of grain (flax, barley, wheat, oats etc.) which is harvested in Spring;
  • Maturity of the grain harvest: The grain seeds are declared mature for harvest once they have reached full growth and have filled with the necessary starch;
  • Migratory patterns of the birds: Birds which flew south for the winter season will begin heading back north in the Spring;
  • Synchronization of the new moon with the turns of the year, Spring and Fall: The First Month must begin in the Spring. Counting from the first new moon closest to the arrival of the Vernal (Spring) Equinox, the seventh new moon in the sequence must occur close to the arrival of the Autumnal (Fall) Equinox on approximately September 22-23. If the next new moon after the twelfth new moon arrives more than one week prior to the Vernal (Spring) Equinox, then the count of the first new moon for the new year is delayed by one lunar month until the following new moon immediately afterward. In this scenario, a closing lunar year acquires a 13th new moon. This is done so that the mo’edim will be celebrated in their appropriate seasons, Spring and Fall. Pesach and Chag HaMatzot (Feast of Unleavened Bread) must be celebrated in the Spring. Yom Teruah, Yom HaKippurim, and Sukkoth must be celebrated in the Fall. If the 13th new moon is not added to the closing lunar year, over time the seasons will move out-of-sync.

In ancient times, the priests of Israel were tasked with the responsibility of determining when the mo’edim would occur during the course of the year. As a result of the Assyrian, Babylonian, Persian and Roman exiles, the Levitical priesthood is no longer accessible to the majority of the B’nai Yisrael community in the Diaspora. Fortunately, however, increased knowledge and technology enable us to know when the mo’edim will occur. There are a number of resources at our disposal which enables us to know when the mo’edim will occur. For example, hebcal.com is an electronic Hebrew calendar that displays all the dates for the mo’edim and other holidays. The annual Old Farmer’s Almanac and websites such as timeanddate.com and calendar-12.com publish the dates of the lunar phases, the equinoxes, and solstices for the upcoming year. These resources, however, do not absolve our community of learning about the signs in nature given by The Creator of how to determine the seasons. He wants us to learn as much as possible about nature as it is His Creation, and we dwell in and interact with nature at every moment.

The Gezer Calendar – Practical Application of the Pre-Exilic Civil Hebrew Calendar

The Gezer calendar inscribed in Proto-Canaanite or Paleo-Hebrew. Image credit: By oncenawhile – Istanbul Archaeology Museums, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=34520838

The Gezer calendar gives some insight into how the ancient Canaanites and Israelites structured their civil year based upon the civil lunisolar calendar. Found in 1908 by Irish archaeologist R.A. Stewart Macalister in the ancient Canaanite city of Gezer, 20 miles west of Jerusalem, the Gezer calendar is a small limestone tablet inscribed in either the Proto-Canaanite/Paleo-Hebrew language. Archaeologists date the calendar back to 10th century BCE. The calendar is currently being housed in the Istanbul Archaeology Museums.

The inscription on the Gezer calendar describes the duties to be carried out in each month or bi-monthly such as planting, sowing, harvesting and maintaining crops. The words are written like a rhyme, which has led scholars to believe that the inscription was either a memory exercise or rhyming exercise for children. The following is a translation of the Gezer calendar inscription in English:

“Two months gathering,
Two months planting,
Two months late sowing,
One month cutting flax,
One month reaping barley,
One month reaping and measuring grain,
Two months pruning,
One month summer fruit


Based upon the inscription above, we see that the civil calendar began in the Fall (Ethanim) and ended in the following Summer (Tsahim). The year number increments by one in the Fall. Using the original sidereal system known to the region during ancient times, the following is an example of how the civil year would have looked for the ancient pre-exilic B’nai Yisrael:

Month # Gezer Calendar Inscription Crop Season Month Name Corresponding Gregorian Months
1 Two months gathering Fruits: Grapes, figs, datespomegranates and olives Fall Ethanim (Tishrei) Sep – Oct
2 Fall Bul (Cheshvan) Oct – Nov
3 Two months planting Grains: Wheat, barley, oats, etc. Fall Marpa’im (Kislev) Nov – Dec
4 Winter Pagrim (Tevet) Dec – Jan
5 Two months late sowing Grains: Wheat, barley, oats, etc. Winter Pe’ulot (Shevat) Jan – Feb
6 Winter Hayir (Adar) Feb – Mar
7 One month cutting flax Grains: Flax Spring Aviv (Nisan) Mar – Apr
8 One month reaping barley Grains: Barley  Spring Ziv (Iyyar) Apr – May
9 One month reaping and measuring grain Grains: Wheat, oats, etc.  Spring Mattan (Sivan) May – Jun
10 Two months pruning Fruits: Fruit trees, vines etc. Summer Zabah (Tamuz) Jun – Jul
11 Summer Karar (Av) Jul – Aug
12 One month summer fruit Grapes, figs, datespomegranates, and olives Summer Tsahim (Elul) Aug – Sep

From the above translation and table, we can see that the civil year began in the Fall when the year number incremented by one (1). The first and second months of the civil year, Ethanim (Tishrei) and Bul (Cheshvan), were devoted to the final gathering of the Fall harvest of the fruit usually grapes, figs, datespomegranates, and olives. The third and fourth months, Marpa’im (Kislev) and Pagrim (Tevet) respectively, were devoted to planting grains such as wheat, barley, and oats in the late Fall to early Winter for harvest in the Spring. The fifth and sixth months, Pe’ulot (Shevat) and Hayir (Adar) respectively, were devoted to the continued sowing of grain in mid-to-late Winter. The seventh month of Aviv (Nisan) was devoted to the cutting of the flax harvest in the early Spring. Barley was harvested in the Spring in the eighth month, Ziv (Iyyar), in mid-Spring. Wheat was harvested in the ninth month, Mattan (Sivan), in the late Spring. The tenth and eleventh months, Zabah (Tamuz) and Karar (Av), were devoted to the pruning of fruit trees in the early to mid-Summer. The twelfth and last month of the civil year, Tsahim (Elul), was devoted to harvesting fruit in the late Summer, typically grapes, figs, dates, pomegranates, and olives.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s