When Jesus was describing the "normal Christian life" in the Sermon on the Mount, he emphasized three spiritual disciplines: praying, giving, and fasting. In each instance, he begins the explanation of each discipline with "when you." When you pray, when you give, and when you fast. The implication is obvious - the normal Christian life includes the habits of praying, giving, and fasting.
Richard Foster writes, Fasting can bring breakthroughs in the spiritual realm that will never happen in any other way. God's people fasted in the Bible for various reasons. Immediate guidance needed. Deliverance from the threat of an oncoming enemy or threat. Financial needs. Repentance of sin. Whatever the reason, it is always a means of the Lord's people setting aside a time to ask Him to work in their lives in a special way. The primary reason for fasting, though, must be fixed in our minds and hearts. The primary purpose is simply to draw near to the Lord.
Charles Spurgeon, pastor of the Metropolitan Tabernacle in London, wrote, Our seasons of fasting and prayer at the Tabernacle have been high days indeed; never has Heaven's gate stood wider; never have our hearts been nearer the central Glory.
Years earlier, John Wesley declared, it was not merely by the light of reason that the people of God have been, in all ages, directed to use fasting as a means: but they have been taught of it of God Himself, by clear and open revelations of His will. Now, whatever reasons there were to quicken those of old, they are of equal force still to quicken us.