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Why Is 40 Days and 40 Nights Special in the Bible?

  • Joel Ryan Contributing Writer
  • Updated Jul 11, 2022
Why Is 40 Days and 40 Nights Special in the Bible?

If you’ve ever read through the Bible, whether chronologically or cover to cover, you may have noticed it uses various numbers that seem to carry weight and even symbolic meaning.

Numbers like three, seven, and twelve all play an important role in the events of the biblical narrative. In many instances, they also highlight important truths and reveal just how orderly and purposeful God is in His design and plan for creation.

For years, Christians have looked to numbers in the Bible to try and discern their greater meaning and connection to other passages of Scripture.

Sometimes, our conclusions are entirely aligned with correct biblical interpretation; many times,  they are not.

We must be careful, therefore, not to try and impose greater meaning onto numbers in the Bible where there is none. Sometimes numbers are just numbers. Taking them out of context or trying to connect them to other passages or themes is not only unwise, but it can also be dangerous.

However, when studied and applied properly, biblical numbers can add incredible insight into our study of Scripture and God’s character. 

One number we often see used in the Bible is the span of 40 days and 40 nights, mentioned in both the Old and New Testaments.

But why is the span of 40 days and 40 nights special, and what does it mean?

Where Does the Bible Mention 40 Days and 40 Nights?

The span of 40 days and 40 nights is referenced in both the Old and New Testaments no less than twenty-four times. 

A few notable examples include:

- The 40 days and 40 nights of rainfall that covered the earth during the Great Flood (Genesis 7-8).

- The 40 days and 40 nights Moses spent on Mt. Sinai on two separate occasions (Exodus 24:18; Exodus 34:28; Deuteronomy 9:9-25).

- The 40 days the spies of Israel spent scouting the Promised Land beyond the Jordan River (Numbers 13:25).

- The 40 days the Philistine giant Goliath taunted the armies of Israel in the Valley of Elah (1 Samuel 17:16).

- The 40 days the prophet Elijah traveled in his flight from Queen Jezebel until he reached Mount Horeb (1 Kings 19:1-8). 

- The 40 days the prophet Ezekiel lay bound and on his side as a symbolic lesson of the forty years of unrighteousness that had plagued and crippled the house of Judah (Ezekiel 4:6).

- The 40 days and 40 nights that Jesus fasted in the wilderness and was tempted by the devil before beginning His public ministry (Matthew 4:1-11; Mark 1:13-14; Luke 4:1-13).

- The 40 days after that Jesus spent with His disciples after His resurrection (Acts 1:3).

Each of these examples references a specific period in the Bible. On their own, they may not seem to have much connection. However, from these instances, a pattern and powerful theme emerges.

What Does the Number 40 Mean in the Bible?

Several theologians have noted that a period of 40 days in the Bible “signifies the completion in the realization of an event.” The idea here is that 40 days often marks an intentional, prolonged, and fixed period in which God solidifies something in the hearts and minds of His followers, sharpening their focus in preparation for something to come. 

Of course, God can make His will known and His instructions clear in far less than 40 days. However, as humans, we tend to forget things, even the miracles of life, and it’s not uncommon for us to question or doubt the things we’ve seen with our own eyes over time, especially if they happened rather quickly. 

That doesn’t mean that we always require a prolonged experience, whether positive or traumatic, for something to be real, memorable, or complete in our lives. However, in the Bible, God sometimes uses a span of 40 days to make sure His people understand that what they have experienced and what He is doing is, in fact, real and preparing them for the season ahead. 

For example, it would take 40 days of taunting from the Philistine giant to Goliath to utterly humiliate and expose the faithless leadership of the armies of Israel. Nothing had changed for Goliath over the span of 40 days. He was as big and mean as he was the day before. But for 40 days, the physical reality of what Israel was up against had become very real in the hearts and minds of its people, the soldiers fled in fear (1 Samuel 17:25).

And yet, at the end of 40 days, God would bring a lowly shepherd boy with a completely different perspective and assessment of the situation to the frontlines. Where the Israelites saw a giant and certain defeat, we know that David saw an opportunity for God to move and deliver His people.

From his prolonged experience tending and defending his sheep, David learned to trust in the Lord and look to Him in all things (1 Samuel 17:36-27).

As David said to the Philistine giant, “you come to me with a sword, a spear, and a saber, but I come to you in the name of the Lord of armies, the God of the armies of Israel, whom you have defied. This day the Lord will hand you over to me… so that all the earth may know that there is a God in Israel,  and that this entire assembly may know that the Lord does not save by sword or by spear; for the battle is the Lord’s, and He will hand you over to us!” (1 Samuel 17:25-27)

We know what happens next.

It took 40 days of Israel’s fear and trembling for God to introduce a different kind of hero, a man after His own heart, upon whom His anointing would be publicly confirmed with a slingshot and well-aimed stone. After 40 days, one thing had been made abundantly clear to all, God does not see as man sees, since man looks at the outward appearance, but the Lord looks at the heart” (1 Samuel 16:7).

Similarly, after the Resurrection, Jesus would spend an additional 40 days on earth with His disciples. At this point, there was no denying that Jesus had risen from the grave. The disciples had time to sit with Him, eat with Him, ask Him questions, and feel His scars. 

During this span, all of their previous doubts had been settled, and questions about who He was answered. After 40 days, the disciples’ faith would be solidified in stone, preparing them for the church-building ministry that was to come.

When Is 40 Days and 40 Nights Associated with Judgment? 

There are, of course, several instances where 40 days and 40 nights can be linked to God’s judgment. However, it is important to recognize how the goodness of God often exists even amid His sovereign judgment. 

For example, the prophet Ezekiel had bound himself and laid on his side for 40 days in public as a symbol of Judah’s sin and apostasy towards God (Ezekiel 4:6). Here, God used Ezekiel’s object lesson as a warning of coming judgment and a call to repentance.

Likewise, God had previously decided to cleanse the earth of its wickedness and start fresh with Noah and his descendants by covering the earth in a Great Flood (Genesis 7-9). While the 40 days and 40 nights of rain made clear that this was truly a universal flood designed to cover the surface of the earth, the focus coming out of the flood was on the fresh start, second chance, and new covenant offered to humanity through Noah. 

Furthermore, for forty years, the nation of Israel would wander in the desert as punishment for their refusal to enter the Promised Land out of fear. Why forty? We know from Scripture that forty years was the time given to coincide with the 40 days the spies had scouted the land. 

For their doubt and disobedience, the people would wander. But at the end of the forty years, God’s heart for His people was again made clear. Have I not commanded you? Be strong and courageous! Do not be terrified nor dismayed, for the Lord your God is with you wherever you go.” (Joshua 1:9)

It took forty years for Israelites to learn that it’s far better to venture forward into the unknown and take risks with God at their side than wander in the deserts of life in fear without Him. 

How Did People Fast for 40 Days and 40 Nights?

In the Bible, fasting occasionally accompanied the span of 40 days and 40 nights.

Fasting, of course, was a common practice. For many Christians, it still is today. Most fasts, even those described in Scripture, are partial, involving fasting from food or other disciplines for a limited time in tandem with focused prayer.

Jesus, we know, spent 40 days being tempted by the devil in the wilderness, and Luke tells us that during this time, “Jesus ate nothing.” (Luke 4:2)

For these 40 days, Jesus withstood every temptation of the devil that had previously been the downfall of every descendent of Adam before Jesus. His ability to overcome temptation, however, affirmed Jesus as the perfect, sinless Son of God and “second” Adam, who would soon redeem what the first had broken. His time alone in the wilderness was a key moment in preparing Him for His public ministry. 

On rare occasions, individuals might partake in an absolute fast from food and water (Ezra 10:6; Esther 4:16: Acts 9:9). Rarely, however, would they do so for longer than three days. 

In his flight from Queen Jezebel, Elijah went without food (and possibly water) for 40 days until he eventually reached Mount Horeb (1 Kings 19:8).

On two separate 40-day periods, Moses also abstained from food and water while in the presence of God on Mt. Sinai (Deuteronomy 9:9; Exodus 34:28). In one instance, Moses had received the Ten Commandments; in the other, he had returned to the mountain after the people had abandoned God and forged the golden calf. It’s quite possible that both periods happened in relatively short succession. 

Of course, this begs the question: how is a 40-day fast from food and water even possible? Apart from the supernatural, it is not. As Arthur Wallis notes in his book God’s Chosen Fast, “the absolute fast is an exceptional measure for an exceptional situation. It is something usually reserved for spiritual emergencies.” (20-21).

For Moses, receiving the Ten Commandments certainly fit the bill as an exceptional situation, arguably one of the most important in the Old Testament.

Furthermore, if both Moses and Elijah partook in a forty-day fast from food and water, there is reason to believe that this was yet, “another striking parallel between these two leading representatives of the old covenant, Moses the giver of the law and Elijah its restorer” (Wallis 20).

With Jesus ushering in the new covenant, it’s also appropriate and symbolic that the Son of God would begin His ministry with a similar forty-day fast, eclipsing what even Moses and Elijah had accomplished through His perfect, sinless life.

The important thing to remember, however, is the way God used the forty-day period in the Bible to make clear His plans, make real His presence and truth, and make ready His followers for future ministry.

Further Reading:

Wallis, Arthur. God’s Chosen Fast. Fort Washington: Kingsway Publications, 1968.

What Is the Significance of 40 in the Bible?

Photo Credit: Getty Images/Mike_Pellinni 


Joel Ryan is an author, writing professor, and contributing writer for Salem Web Network and Lifeway. When he’s not writing stories and defending biblical truth, Joel is committed to helping young men find purpose in Christ and become fearless disciples and bold leaders in their homes, in the church, and in the world.