Fasting can be defined as abstaining from food or certain types of food for a period of time for the purpose of drawing closer to God. Sometimes believers fast in an attempt to determine the will of God. There are passages in the Bible that speak about fasting.
Jesus
Jesus fasted for forty days while being tempted of the devil:
Jesus, full of the Holy Spirit, returned from the Jordan and was led by the Spirit in the desert, where for forty days He was tempted by the devil. He ate nothing during those days, and at the end of them He was hungry (Luke 4:1-2).
Unlike most fasts, Jesus did not eat anything during His forty days in the wilderness.
Moses
Moses fasted also for forty days:
Moses was there with the LORD forty days and forty nights without eating bread or drinking water. And he wrote on the tablets the words of the covenant - the Ten Commandments. (Exodus 34:28).
No Explicit Command
While fasting was practiced by Jesus and His disciples, there is no explicit command in the New Testament for believers to fast.
In fact, there is only one place in the entire Bible where fasting is commanded-one day a year on the Day of Atonement.
Disciples Would Fast
Jesus, however, did indicate that His disciples would fast after He left the world.
Then John's disciples came and asked Him, How is it that we and the Pharisees fast, but your disciples do not fast? Jesus answered, How can the guests of the bridegroom mourn while he is with them? The time will come when the bridegroom will be taken from them; then they will fast (Matthew 9:14-15).
Privately
If the believer does chose to fast there are certain things that should be remembered. First, the fast is a private matter-it is between the believer and God. Jesus made it clear that no one should know when we are fasting.
When you fast, do not look somber as the hypocrites do, for they disfigure their faces to show men they are fasting. I tell you the truth, they have received their reward in full. But when you fast, put oil on your head and wash your face, 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 (Matthew 6:16-18).
Specific Reason
In addition, there should be a specific purpose behind the fast. It should be centered on a specific need that needs to be addressed in serious prayer.
The religious leaders in Jesus day made the mistake of routinely fasting. This missed the reason why fasting was instituted.
No Physical Work
When fasting it is best not to be engaged in strenuous physical activity. Since fasting takes away our physical strength we should not spend the time being engaged in some physical activity. This will defeat the purpose.
Use Common Sense
We also need to remind ourselves to use common sense when we fast. God has given us a brain and expect us to use it. Therefore we should not take any unnecessary physical risks. If a person is at risk physically, then fasting should not be an option.
Summary
When we choose not to eat certain food or food in general for a period of time there are several things they should keep in mind. First, it should be done privately between the believer and the Lord-there should be no outward show that we are fasting.