The Hillel II Calendar and Double Torah Portions

The Hillel II calendar is the fixed, calculated Hebrew calendar that Jewish communities around the world still use. Tradition dates it to 359 CE. It is connected to Hillel II, the patriarch (nasi) of the Jewish community in the land of Israel, and to the Sanhedrin of his day. It follows the moon for its months and the sun for its seasons, so some years need a thirteenth month. That extra month is also why certain double Torah portions, like Vayakhel and Pekudei, are split apart in a Hebrew leap year.

So if you noticed Vayakhel-Pekudei read as one portion one spring and as two portions the next, nothing is wrong. The reading cycle is simply fitting itself to a longer year.

A calendar with two masters: the moon and the barley

The Torah does not hand Israel a simple solar calendar like our Gregorian one. It does not hand Israel a purely lunar calendar either. It ties worship to both.

Passover belongs to the month of Aviv. "Observe the month of Aviv and keep the Passover to the Lord your God" (Deuteronomy 16:1). Aviv is more than a name. It describes grain at the stage of ripening. Exodus 9:31 uses the same word when it says the barley in Egypt "was in the ear." Passover is meant to come in the spring, when the barley is ripening.

The new moon matters just as much. Numbers 10:10 speaks of blowing trumpets "in the beginnings of your months." Numbers 28:11 sets offerings for the start of each month. Psalm 81:3 calls for the shofar at the new moon.

Here is the difficulty. Twelve lunar months come to about eleven days less than a solar year. Follow only the moon, and the feasts slide backward through the seasons, as they do in the Islamic calendar. Follow only the sun, and your months stop beginning at the new moon. The Hebrew calendar has to keep both.

Its answer is to count lunar months and, in certain years, add one more month so Passover lands back in the spring. For the bigger picture of how the appointed times fit together, see God's Biblical Calendar.

Before Hillel II: witnesses, a court and messengers

For centuries the new month was declared, not calculated. The Mishnah describes the process in tractate Rosh Hashanah, chapters 1 and 2. Witnesses who had seen the new crescent came to the court and were questioned. Then the court sanctified the month, and word had to be sent out to other communities.

The court also decided when a year needed an extra month. The Talmud discusses this at length in Sanhedrin 10b to 12b. The reasons it weighs include whether the barley is ripe and the season has turned, and practical matters like the state of roads and bridges for pilgrims coming up for Passover.

That system worked while Jewish life was centered in the land and messengers could reach the communities. After the destruction of the Second Temple in 70 CE, and as Jewish communities spread across the Roman world and into Babylon, it became harder and harder to keep everyone on the same dates.

This was not a small worry. The feasts of Leviticus 23 are mo'adim, appointed times for the whole people. If one community keeps Passover on one day and another community a day later, Israel no longer stands before God together.

What Hillel II put in place

The fixed calendar solved that problem. Any community could work out the months and feasts on its own, without waiting for word from the land of Israel, and still arrive at the same dates as everyone else. Jerusalem, Babylon, North Africa and Europe could all keep Passover on the same night.

A few features are worth knowing:

• A 19-year cycle. In seven of every nineteen years, an extra month is added. That added month is called intercalation, which sounds technical but just means slipping in another lunar month so the moon catches up with the sun.
• Two months of Adar. In a leap year the month of Adar is doubled into Adar I and Adar II. Nisan, the month of Passover, still follows right after.
• Small adjustments. The calculation allows a day to be added or subtracted from a year when needed. This keeps Yom Kippur from falling on the day before or after a Shabbat, and keeps the Hoshana Rabbah processions with lulav and willows from falling on Shabbat.
• Real accuracy. Its months average about 29.5 days. Its years average about 365.2468 days, against a solar year of about 365.2422.

Tradition holds that instituting this calendar was one of the last great decisions of the Sanhedrin before it ceased to function. For the same reason, traditional Jewish teaching holds that a return to declaring months by sighting would take the authority of a reconvened Sanhedrin. The point is not only astronomy. It is about who speaks for all Israel, and keeping the people together.

A fixed calendar did not throw out the biblical calendar. It is a way of keeping the biblical calendar under the conditions of exile. The months are still lunar, Passover still comes in the spring, and the feasts of Leviticus 23 still come in their order.

The weekly Shabbat was never part of the calculation at all. It follows the seven-day week of Genesis 2:2-3 and Exodus 20:8-11, not the moon, and the calendar does not restart the week each month.

Why a Hebrew leap year adds a whole month

A Gregorian leap year adds one day, February 29. A Hebrew leap year adds a month. The difference comes from what each calendar is trying to do. The Gregorian calendar only has to stay with the sun. The Hebrew calendar has to stay with the moon and with the seasons at once.

The extra month comes right before Nisan, because Nisan is the month the religious year turns on. "This month shall be unto you the beginning of months" (Exodus 12:2). If Nisan arrived while it was still winter, the calendar would have missed the very thing it exists to protect.

The Hillel II calendar in 2026

A civil year always overlaps two Hebrew years, and that is where searches for the Hillel 2 calendar in 2026 tend to get tangled.

• January to September 2026 falls in Hebrew year 5786. That is a regular twelve-month year, so in spring 2026 Vayakhel and Pekudei are read together.
• Rosh Hashanah in September 2026 begins Hebrew year 5787. That is a leap year, with both Adar I and Adar II, so the portions that usually pair up get more room in spring 2027.

How the weekly Torah readings fit the year

The parashot, the weekly Torah portions, carry a congregation through all five books of Moses in a year. The cycle ends with the last verses of Deuteronomy and starts again at Genesis on Simchat Torah, right after Sukkot.

There are 54 portions, but no year gives you 54 ordinary Shabbats to read them. Some Shabbats fall on festivals, which have their own readings. Some years are shorter than others. Outside the land of Israel, certain festivals are kept for two days, so a festival day can land on a Shabbat abroad but not in Israel. That is why the two schedules sometimes differ for a few weeks.

The solution is the double portion: two portions read together on one Shabbat. The pairs that can be combined are:

• Vayakhel-Pekudei
• Tazria-Metzora
• Acharei Mot-Kedoshim
• Behar-Bechukotai
• Chukat-Balak (sometimes, outside the land of Israel)
• Matot-Masei
• Nitzavim-Vayelech

Not every pair is combined every year. The schedule joins or separates them as needed so the whole Torah is read in order and the cycle finishes on time. If this rhythm is new to you, Introduction to Weekly Torah Portions is a good place to begin.

Vayakhel and Pekudei: together one year, apart the next

These two close the book of Exodus. Vayakhel opens at Exodus 35:1, where Moses gathers the people and repeats the command of Shabbat before the work on the tabernacle begins. Pekudei opens at Exodus 38:21 with the accounting of everything given for the tabernacle.

In a regular year there usually isn't room for both, so they are read together. In a leap year the added month brings several extra Shabbats. Vayakhel and Pekudei can then each have their own week, and so can Tazria and Metzora, Acharei Mot and Kedoshim, and Behar and Bechukotai, depending on how that year falls.

That is all that is happening. Nothing in the Torah changes, and no Shabbat is lost or added. The reading plan is simply being fitted to the year God's people are actually living. There is something lovely in it, too. In a short year the congregation reads a little faster. In a long year it slows down. Either way, everyone moves through the Torah together.

What the calendar keeps for us

The Hillel II calendar keeps unity. A family in Jerusalem, a synagogue in Brazil and a congregation in Ohio can all open to the same portion on the same Shabbat.

It also keeps the feasts tied to the story the Bible tells. Passover stays in the spring. Shavuot stays fifty days out from it; if you are counting, How To Count the Omer 2026 walks through the days. Sukkot stays at the ingathering at the turn of the year (Exodus 23:16).

The Talmud's long debates about intercalation are worth knowing even for believers who do not treat the Talmud as Scripture. They show how carefully Jewish communities wrestled with obedience, testimony and authority. The Talmud Explained for Believers is a careful introduction.

Why a disciple of Yeshua should care

Yeshua (Jesus) lived by this calendar. His parents went up to Jerusalem "every year at the feast of the Passover" (Luke 2:41). John 7 places Him in Jerusalem at Sukkot, and John 10:22 at the Feast of Dedication, Hanukkah. Passover frames His last week, His death and His resurrection.

The apostles kept the same rhythm. Acts 2 takes place at Shavuot. Paul hurried to reach Jerusalem by Shavuot if he could (Acts 20:16), and he planned to stay in Ephesus "until Pentecost" (1 Corinthians 16:8).

You do not need to become Jewish to learn this calendar. It simply lets you hear the timing of the text: why a feast gets mentioned, why the roads were crowded, why the apostles reckoned time the way they did.

So the next time two portions are read together, ask what kind of year you are in. And when a double portion is split, take it as a gift. Read Vayakhel one week and Pekudei the next, slowly, and notice how much is there when you give each portion its own Shabbat.

Questions people ask

What is the Hillel II calendar?

It is the fixed, calculated Hebrew calendar used by Jewish communities today. Tradition dates it to 359 CE under Hillel II and the Sanhedrin. It uses lunar months and adds a thirteenth month in seven of every nineteen years so Passover stays in the spring.

Who created the Jewish calendar?

The foundations come from the Torah: new moons, Shabbat and the appointed feasts tied to the seasons. For centuries a court in the land of Israel declared each month from witness testimony. The fixed, calculated form used today is traditionally credited to Hillel II and the Sanhedrin in the fourth century CE.

Why are some Torah portions read as double portions?

There are 54 weekly portions, but no year has 54 ordinary Shabbats available for them, since some Shabbats carry festival readings. Pairs such as Vayakhel-Pekudei or Matot-Masei are read together so the whole Torah is finished on schedule.

Why do double Torah portions split in a Hebrew leap year?

A Hebrew leap year adds a thirteenth month (Adar I and Adar II), which brings several extra Shabbats. With more weeks available, portions that are usually combined, such as Vayakhel and Pekudei, can be read separately.

Is 2026 a leap year on the Hillel II calendar?

The civil year 2026 overlaps two Hebrew years. Hebrew year 5786, which runs until September 2026, is a regular year. Hebrew year 5787, which begins at Rosh Hashanah in September 2026, is a leap year with Adar I and Adar II.