Why Did Jesus Teach His Disciples to Fast? Matthew 6:16-18

Fasting

Besides giving and praying, fasting was one of the other major spiritual disciplines for Jewish believers in Jesus' day.  Jesus had spoken to giving and praying, now he turns to fasting.  We know Jesus fasted 40 days in the wildnerness before he started his ministry.

Moses fasted from food and water for 40 days in the wildnerness before receiving the Ten Commandments. The early church fasted and prayed before setting apart Saul and Barnabas for the work of the ministry.   Fasting was also practiced leading to times of repentance when people turned back to God, after a period of disobedience to Him. 

"Even now," declares the Lord, "return to Me with all your heart, with fasting and weeping and mourning." Joel 2:12 (NASB)

The basic idea of fasting is to abstain from an earthly pleasure in order to focus more on your relationship with God.  Most often it is a fast from "food" as this is the basic necessity life. Importantly it is not as much about "giving up something" in and of itself, "but giving up something" in order to draw nearer to God and His power.  I.e. To be able to do with God, what you can't do by yourself.

16 “When you fast, do not look somber as the hypocrites do, for they disfigure their faces to show others they are fasting. Truly I tell you, they have received their reward in full. 

Notice Jesus says, "When you fast".  He acknowledges it is a good thing to do and assumes they would do it. But the problem was that they were doing it with wrong motives, namely to be noticed and praised by others.  The word "hypocrites" comes from the Greek word for "actor". In Greek plays actors and actresses wore masks to show they were acting.  Today we might call them "posers". Hypocrites "play act" being a Christian.  After the take off their mask they go back to their old selves no different than anyone else.   

Jesus says when they received the applause by men, they had received their reward in full.  Their desire to draw near to God and his power were nullified because their motives were selfish. 

17 But when you fast, put oil on your head and wash your face, 

On the contrary, Jesus taught them to wash their face and put on oil, so nothing about their appearance seemed out of the ordinary.  Jesus knew we are so prone to turn our works to pride, that he teaches them to avoid the temptation of, "Oh are you fasting today??"  

This happens with other good works too.  We may be serving the poor, but more interested in others noticing us than actualy serving those in need. I heard a quote that went something like this,

 "Sometimes the pursuit of virtue is just as bad as than the pursuit of vice just because it gets everybody's attention."  

18 so that it will not be obvious to others that you are fasting, but only to your Father, who is unseen; and your Father, who sees what is done in secret, will reward you.

Though it is natural for us to live in the natural or physical world, God lives in the spiritual world.  We gravitate to things we can see and hear, taste and touch.  There is nothing wrong with getting a compliment or affirmation from someone else.  We are all wired to need encouragement but I don't think this is what Jesus is talking about.  

If our true desire is to fast and grow closer to God and experience his power, when we focus on ourselves we lose sight of the true reward for any spiritual discipline.  Being with God or engaging in spiritual disciplines is for the purpose of doing things we could never do in our natural power or personality. 

Dallas Willard says this about "discipline", 

"Discipline, strictly speaking, is activity carried on to prepare us indirectly for some activity other than itself. We do not practice the piano to practice the piano well, but to play it well."

Dallas also says this in his classic book, "The Spirit of Disciplines", 

"The greatest need you and I have—the greatest need of collective humanity—is renovation of our heart. That spiritual place with in us from which outlook, choices, and actions come has been formed by a world away from God. Now it must be transformed. Indeed, the only hope of humanity lies in the fact that, as our spiritual dimension has been formed, so it also can be transformed."

As we use the discipline, or we might say  the gift of fasting", may it lead us closer to God and more equipped to do the works he has called us to with His power and His love.  Our reward for fasting in the way Jesus teaches is not only a better relationship with God today but we are storing up treasures for evermore.