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Fasting in Jesus' Sermon on the Mount

I am a Christian pastor who wishes to bring glory to God in all that I do, and to help people through my writing to know Him better.


Introduction: Fasting in the Biblical Era

American culture in general knows very little about the ancient practice of fasting. The average American eats about 2,000 pounds of food every year, and as a result, is overfed and undernourished. came out with a graphic showing how that food is dispersed in the American diet. Some of the results may be surprising. Here are their findings:


Dairy comes up as the most consumed food on the list. Americans average more than 800 pounds of milk, cheese, and other non-cheese dairy products.


Vegetables come second on the list at more than 400 pounds per year. But don’t let that number make you feel that American’s are eating enough vegetables. When you combine all the meat, fats, oils, sugar and flour, vegetables are vastly outnumbered.


Americans eat 273.2 pounds of fruit every year. Is anyone else surprised that we eat more vegetables than fruit?

Coffee, Cocoa & Nuts

The study says Americans eat 24 pounds of this stuff. Seems a bit low?

Fats and Oils

85.5 pounds of fats and oils are consumed every year by the average American.

Red Meat

Americans eat 110 pounds of red meat, 62 pounds of beef and 46 pounds of pork.


Americans eat 73.6 pounds of poultry — 60 pounds of that number is chicken.

Fish and Shellfish

Americans on average eat 16 pounds of fish and shellfish.


About 33 pounds of eggs are consumed each year by the average American.

Flour and Cereal Products

The average American eats 192.3 pounds of flour and cereal products — about 134 pounds of that is wheat flour.

Caloric Sweeteners

The average American eats 141.6 pounds of caloric sweeteners. Unfortunately, 42 pounds of that is corn syrup.

Those Numbers Include:

  • 29 pounds of French Fries
  • 23 pounds of pizza
  • 24 pounds of ice cream
  • 53 gallons of soda — about a GALLON A WEEK!
  • 24 pounds of artificial sweeteners
  • 2.736 pounds of sodium, 47% more than what’s recommended
  • 0.2 pounds of Caffeine (90,700 mg)– there’s about 50 mg in a can of Coke
  • 2,700 calories per day

In contrast, in the Biblical era, food was at times in short supply, especially in seasons of famine. And people didn't have refrigeration, freezing or the modern canning methods that we possess today. Therefore, they were not able to store it as easily as we do. And it goes without saying that they didn't have the supermarkets that we have in the United States.

So, in the Ancient Near Eastern cultures, fasting was a bigger deal than it is today. It demonstrated a reliance on God, or the gods if you were from another culture other than Israel. Fasting in the Bible can generally be viewed as an example of religious activity that would have been common in any number of the other cultures surrounding God's people throughout Biblical history.

In Jesus' famous Sermon on the Mount He discusses fasting in Matthew 5:16-18. And He warns His listeners that this practice is often used by hypocrites who say that they love the Lord and are His followers but aren't really being truthful. These hypocrites rather use fasting in order to bring attention to themselves and not to give God the glory He is rightfully due.

In order to understand how this passage can be rightly divided or correctly handled, as Paul would say in II Timothy 2:15, we who live in the 21st century first have to know what the ancient practice of fasting was and what it was used for in the biblical world. Then we must see why the Lord brought up the subject in the first place in His sermon. We also have to ask if fasting applies to us today? In other words, are we required to fast as God's people, the church. Finally, we must see if there are any principles which we can still apply to us in our modern world in which we live.

Let us begin by defining fasting.

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I. Definition and Uses of Fasting

Fasting may be defined as self-denial by going without food for a period of time. It may be total or partial -- avoiding certain foods or eating smaller than normal quantities. The origin of fasting as a religious practice is unclear, but both the Old and New Testaments of the Bible mention a number of instances of fasting for various reasons. These include the following:

  1. Distress or Grief: A natural reaction to mourning, distress and grief is fasting. For example, there was a seven day fast over the death of Saul in I Samuel 31:13. Also, as the apostle Paul was being transported to Rome as a prisoner the ship was caught in a violent storm. Fearing death, those aboard did not eat for many days (Acts 27:18-20, 33-34).
  2. Spiritual Preparation: Fasting can also be seen as a self-sacrifice that makes one humble and more accepting of God's will. In the Old Testament Moses fasted for forty days in preparation for receiving the Ten Commandments (Exodus 34:28). Also, Elijah fasted forty days before speaking with God (1 Kings 19:8). And in the New Testament Jesus fasted for forty days in preparation for His temptation by the devil (Matthew 4:1-11, Luke 4:1-13). Paul also fasted 3 days after his conversion (Acts 9:9).
  3. Repentance and Atonement: Sometimes people would sin and show their repentance through prayer and fasting before the Lord. When Jonah predicted that God would destroy Ninevah the Ninevites fasted as a sign of repentance, hoping that the Lord wouldn't follow through with His warnings. God saw their repentance and spared them (Jonah 3:3-9). The Day of Atonement was the only yearly obligation in the Law of Moses that commanded the people of Israel to fast. They were also to rest on that day as well (Numbers 29:7). However, if you read through the Old Testament, Israel would often humble themselves and fast in order to regain God's favor after they sinned (Judges 20:26; I Samuel 7:6).

In the passage that we are looking at today Jesus teaches that fasting, like prayer which He talked about earlier in this sermon, should be done in private and not for show (Matthew 6:16-18, cf., Matthew 6:5-7). We can also see in the Gospels that John the Baptist's disciples fasted according to Jewish tradition, but Jesus' followers didn't. However, Jesus did mention that His followers would mourn and fast after He left them ((Matthew 9:14-15; Mark 2:18-20; Luke 5:33-35).

Throughout the Bible many of the biblical characters were seen to fast. Even the Apostle Paul, as we noted earlier, did as well. Besides his conversion he tells the Corinthians, in his first book to them that he suffered for Christ and by this he proved that he was a genuine apostle of the Lord. One of the things he did was to go without food. In I Corinthians 11:27 he continues a long string of things that showed proof that he was a true minister of the Lord which included such things as beatings and imprisonment. 11:27 tells us:

"in weariness and toil, in sleeplessness often, in hunger and thirst, in fastings often, in cold and nakedness—"

So we see that the Bible has a rich tradition of fasting all through it.

And yet, with all of this tradition in the Bible, neither Jesus nor His disciples made it mandatory. There are no commands to do it in the New Testament, including all 13 of Paul's epistles.

With that in mind, let us look further into what Jesus has to say in his sermon.

II. Jesus' Use of the Concept In His Sermon

Here are the words of our Lord that He spoke:

"Whenever you fast, do not put on a gloomy face as the hypocrites do, for they neglect their appearance so that they will be noticed by men when they are fasting. Truly, I say to you, they have their reward in full. But when you fast, anoint your head and wash your face, so that your fasting will not be noticed by men, but by your Father who is in secret; and your Father who sees what is done in secret will reward you." (Matthew 6:16-18).

As we said earlier, Jesus never made it mandatory for His disciples to fast. He just said that when you do fast you should do it in a certain way. And we have to point out that the main point of this passage isn't fasting here anyway. The point is the same as the prior verses in which he talked about prayer (Matthew 6:5-15). It is that a true follower of Christ is not to be hypocritical, saying one thing and doing another. They shouldn't say or do things that appear to be done for the Lord but are really an attempt to bring glory to self and make you look good to others.

Some of Jesus' most harsh words were said about hypocrisy. Jesus pronounced woes in Matthew 23 to the hypocritical teachers of the law and Pharisees many times. And in Matthew 23:23 he even called them a 'brood of vipers.'

God's people should not be like these evil men. Everything we do shouldn't be to glorify self, but to magnify the Lord.

Those hypocrites who fast for others to see only get rewarded on this earth by the fickle praise of those who don't really care much about them anyway. On the other hand, what you do for the Lord, even in secret where no one but He knows about it, you will receive an eternal reward in heaven.

So, in that sense, it doesn't matter whether you think a Christian should fast or not. The principle is the same in the 21st century Church as it was back then. What we do should cause men to seek God and not us. We shouldn't distract people from giving God all the glory. We should never take the praise for ourselves that rightly belongs to Him.

III. Fasting And Today's Believers

However, having said all that, what do we make of fasting for members of the Body Christ today? Modern church teachings about fasting vary. It is interesting that many Catholics observe partial fasting traditions during Lent (the period between Ash Wednesday and Easter). Orthodox Christians observe even more fasting days. However, most Protestant churches do not have any firm rules or traditions about fasting.

Because of the fact that we cannot find any clear commands in the New Testament, including the Pauline epistles, to fast, I don't believe that fasting is commanded or required of God's people today.

But the truth is that where Scripture is silent we cannot be dogmatic about it. And it is not up to us to tell other Christian traditions that they should or shouldn't fast. Paul talks about not causing a weaker brother to stumble by flaunting my freedom in I Corinthians 8:9. That would include those who consider themselves strong and think that they have the freedom not to fast as well. They shouldn't cause another to stumble and sin if that brother or sister chooses to fast.

I came from a church where fasting wasn't observed or even spoken of much. And to tell the truth, the only time I have ever gone without food, besides some yearly fasting blood draws for physicals, was when our youth group at our church was raising money for an organization that helped the hungry by participating in a 13 hour fast where we got pledges of money from people to go without food for that amount of time. And then we were monitored by a nurse who also made sure we drank enough fluids during that period so we wouldn't become dehydrated.

But despite my lack of fasting in my Christian walk, I believe that my relationship with the Lord is strong and close today. And I am not violating any Scripture since there are none that tell me to do it But that doesn't give me the right to criticize my fellow Christians for their belief in fasting for the Lord..

There is another Pauline passage we can look at here. Romans 14:6. Though it was referring originally to meat offered to idols, as was the first Scripture that I quoted from Paul, I think that it can equally apply to the concept of fasting as well. He states:

"He who observes a special day does so to the Lord; he who eats does so to the Lord, for he gives thanks to God; and he who abstains does so to the Lord and gives thanks to God....."

The bottom line is that whatever we choose to do we are both to give glory to God and do no harm to our fellow believer but edify him, or build him up.

V. Further Principles for the Church

There are a few other principles that we can take from biblical fasting that will help us whether we do it or not. Since food is such a necessary part of life, to voluntarily go without it showed that the person who fasted understood that there is something more than the physical which is also more important even than our daily bread. And that is honoring the God who gives us both life and bread. Jesus summarized it quite well during His temptation in the wilderness when quoting the Scriptures and telling Satan:

"Man shall not live by bread alone but by every word that proceeds out of the mouth of God."

Put differently, fasting directed hunger toward God. It cleared the mind and body of earthly attention and drew the person closer to the Lord. So, they gained spiritual clarity of thought while fasting. It allowed the one who fasted to hear God's voice more clearly. It also demonstrated a profound need of God's help and guidance through complete dependence on Him.

Also, people throughout history have fasted in order to slow down, quiet the noise of the culture around them, and take the time and space to listen and reflect. It allowed the Lord's people to turn their hearts toward God. We also need to slow down as well to give God the attention that is due Him.

These are all timeless truths that go beyond the act of fasting itself. A true Christian seeks God and the eternal because they know that this present world will not last. And we need to remind ourselves of what is truly important in this life and beyond.


In dealing with the concept of fasting, we should observe the wise words of a fellow Christian from centuries ago who said:

"In essentials unity. In non-essentials liberty. In all things charity."

To fast or not to fast is not an essential of the Christian faith. If it were, there would be some commands for it in the New Testament, and especially from the Apostle Paul, the Apostle to the Gentiles. But we should allow our fellow Christians their liberty to fast if they want to do so. Further, we should have charity or love for one another so that we don't become embattled over it one way or the other.

But for those who choose to fast, or to do anything else for that matter, may you follow the admonition of Paul in Colossians 3:17 where he tells us:

"Whatever you do in word or deed, do everything in the name of the Lord Jesus, giving thanks through Him to God the Father."

For when we do this then our choice will bring honor to the one that has given us eternal life. And His honor is why we exist in the first place. Let us praise His name forever!!

© 2021 Jeff Shirley

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