ICEJ The Hebrew Day

The Biblical Calendar and the Prophetic Timeline

By: Karen Engle, ICEJ USA Managing Editor 

Then God said, “Let there be lights in the firmament of the heavens to divide the day from the night; and let them be for signs and seasons, and for days and years; and let them be for lights in the firmament of the heavens to give light on the earth”; and it was so. (Genesis 1:14-15)

As December winds up, many people look forward to a new year, and with it, consider hopes and dreams for accomplishing goals. However, many Bible readers are unaware that the calendar most of the world follows today is not the biblical calendar God set back in Genesis and Exodus—and the new year doesn’t begin in January. Indeed, God has a calendar, and the Bible tells us all about it. His is a different system of days, months, years, and seasons than what we follow today—and there is much we can learn from it about God and how He has operated over time.

Back in ancient biblical times, people did not have digital clocks to track time in hours, minutes, and seconds. And they certainly didn’t have calendars on their phones or hung on walls to alert them to the numbers of days in a particular month or the date of a certain holiday. But they did have a system given to them by God.

The Biblical Calendar: Day, Week, Month, and Year

The principles of God’s calendar go back to Genesis 1, which reveals that on day four of creation, God established the sun, moon, and stars:

“Then God said, “Let there be lights in the firmament of the heavens to divide the day from the night; and let them be for signs and seasons, and for days and years; and let them be for lights in the firmament of the heavens to give light on the earth”; and it was so.” (vv. 14–15)

Notice that God created the “lights in the firmament of the heavens” for light but also for His calendaring system, for signs and seasons, for days and years—in short, for timekeeping. The lunar cycle defined the months, while the solar cycle set the year.


The Biblical Day and Week

In Genesis 1:5 we learn that God called the light day and the darkness night and that “the evening and the morning were the first day.” God also referred to each day as an ordinal: “the first day,” “the second day,” and so on. God’s day is from evening to evening, affirmed with His instruction for celebrating the Sabbath in Leviticus 23:32: “From evening to evening, you shall celebrate your sabbath.” This is why to this day Jews begin the first day of their week at sundown on our Saturday and their seventh day, Sabbath, at sundown on Friday. (See diagram above.)

Obviously, this is quite different from our calendaring system. Our day begins at midnight and ends at midnight, but the biblical day starts in the evening, a portion of time with no light, from sunset to dawn. The second part of the Hebrew day is from dawn to sunset, daylight hours. Thus, the sunrise in the morning was the middle of the Hebrew day; when the sun set, the day ended, and the people started a new day—with darkness.

The Biblical Month

The sun divided the day from night, establishing a biblical day. But the moon provided the division of the month—one new moon to the next equaled one lunar, biblical month. As the moon waned, ending one month, the children of Israel looked for the New Moon—and once sighted, a new month began. We see this in Isaiah 66:22–23, where the prophet hints that this is how God will calculate months in His kingdom to come:

“For as the new heavens and the new earth which I will make shall remain before Me,” says the LORD, “So shall your descendants and your name remain. And it shall come to pass that from one New Moon to another, and from one Sabbath to another, all flesh shall come to worship before Me,” says the LORD.

Interestingly, Exodus 12:2 indicates God numbered the months based on when Israel was released from captivity in Egypt, the very first Passover: “This month shall be your beginning of months; it shall be the first month of the year to you.” It was the Hebrew month Abib—roughly our March/April. Nahum Sarna writes in the JPS Torah Commentary that God did so as a stark visual—Israel would be starting a new order of life dominated by the consciousness of God’s active presence in history: “The entire religious calendar of Israel is henceforth to reflect this reality by numbering the months of the year from the month of the Exodus.”

It was at this same time God formally instituted the Sabbath, linking God’s rest after the six days of creation (Exodus 20:8–11). God would arrange His calendar according to His great acts on behalf of the nation He set apart to bring glory to his name.

Like biblical days, God identified His months using ordinals: “the first month,” “the second month,” and so on. Later, the children of Israel gave them Hebrew names. However, while in Babylonian captivity, Jews borrowed month names from the Babylonian calendar. The first month, Abib, for example, became Nisan.

The Biblical Year

The first month of the year was determined by watching for the ripeness of the early grain, barley, according to the state of maturity called abib (hence the Hebrew name for the first month). At the close of the year, farmers would check the barley’s stage of ripeness, and if too unripe, add a month to the calendar. God’s calendar is thus solar-lunar. The lunar reckoning uniquely tied His calendar to the rain seasons in Israel, which makes sense knowing that God’s feasts, outlined in Leviticus 23, centered on agriculture in Israel and the ripening of certain harvests.

Starting the first month of the biblical year at the correct time was paramount and impacted when Israel would celebrate each feast. For example, Firstfruits required that the priests pick the first ripened fruits of the barley harvest in the later spring to present before the Lord. If God’s people did not set the first month of the year according to His instruction—according to the ripening barley harvest—the first fruits of the barley harvest might not be ready to be picked at Firstfruits.

The Biblical Calendar and Bible Interpretation

Knowing God’s calendar is certainly not a salvation issue. However, it’s what I call a “Bible interpretation aid.” Understanding God’s method of timekeeping can help bring a deeper understanding of not only what day or month He told Israel to celebrate a certain feast or when an event happened, but it illuminates the majesty of His Word. When we understand days, months, and years according to God’s calendaring system, we start to see the exactness of days and times He caused—and still causes—things to happen. And that matters when it comes to Bible prophecy.

Let’s return to that first Passover. Recall that the month the children of Israel came out of Egypt was the first month of the year, and on the tenth of the first month, they were to take an unblemished lamb into their home “until the fourteenth day of the same month,” at which time they were to kill the lamb at twilight (Exodus 12:1–6). This might seem like trivial information—until we consider that when Jesus entered Jerusalem on a donkey and was declared the King of Israel, it was the season of Passover. John 12:1 says that six days before Passover, which would have been Nisan 9, Jesus had been in Bethany with Martha and Mary. “The next day” (v. 12) the blameless Lamb of God chosen before the foundation of the world to take away our sins entered Jerusalem on the tenth of Nisan, the first month. Five days later before sundown on the fourteenth, the Lamb of God was slain. God revealed way back in Exodus the day and month Jesus would be crucified through the shadow of the first Passover.

There are many other examples of specific dates in Scripture, and understanding God’s calendar helps make sense of those dates. Consider just one more, Ezekiel 24:1–2:

In the ninth year, in the tenth month, on the tenth day of the month, the word of the Lord came to me (Ezekiel) saying, “Son of man, write down the name of the day, this very day—the king of Babylon started his siege against Jerusalem this very day.”

Understanding God’s calendar helps us know Babylon’s siege against Jerusalem started in the winter on the tenth day of the tenth month of Tebet.

How We Shifted from the Biblical Calendar

Julius Caesar reformed an existing Roman calendar in 46 BC, calling it the Julian calendar. After the Romans destroyed Jerusalem in AD 70 and the Jews were scattered from one end of the earth to the other, the Roman Empire took control of Judah, and the Julian calendar became the standard. It remained in use until it was reformed again in 1582 under Gregory XIII, further reflecting the solar cycle. This Gregorian calendar is the calendar now in use in most of the world. Over time, the church moved away from the biblical, solar-lunar calendar centered on God’s yearly cycle of festivals to a strictly solar calendar centered around Roman, pagan holidays.

Ultimately, Satan does not want God’s people to follow the biblical calendar because like so many other types and shadows in the Old Testament, it points to Israel’s Messiah and affirms the accuracy of God’s Word. Satan’s goal has always been to lie and deceive. Even Daniel said: “He will think to change times (seasons) and laws” (Daniel 7:25).

Why It’s Important to Understand God’s Biblical Calendar Today

What are Christians to do? Should we move off the current Gregorian calendar and onto the biblical calendar? Practically, that would not make sense; much of the world follows this calendar, and we must be able to function accordingly. However, understanding God’s calendar sheds light on not only Scripture and the timing of events in both the Old and New Testaments, but it helps us understand more deeply what God is doing in our day.

But perhaps the most important reason to understand God’s biblical calendar today is its connection to His feasts. Because all of God’s Feasts point to our Messiah, knowing God’s calendar will only magnify our understanding of those set-apart festivals, giving us a greater understanding of who He is and how perfect His Word. God’s feasts are a shadow of His plan of redemption over all time, and knowing God’s calendar provides incredible “clues” found in His feasts about not just Jesus’ first coming but His second coming too.

The Spring Feasts and Why They Point to What’s Ahead

The Feasts of the Lord and Their Rich, Biblical Significance

Aviv Barley and the Start of the Biblical Year

Feast of Firstfruits—the First and Best of What’s to Come