God promises that through Jesus Christ, prayer and fasting will be duly rewarded. However, contrary to popular belief, the power of fasting has nothing to do with the ability and faithfulness of people who fast, but has everything to do with the ability and faithfulness of God.
Fasting works because it puts us in an attitude of humility, trust and unselfishness. It's not supposed to work because we do it for the sake of doing it, but because we surrender our hearts to the Lord and set aside the time, necessity, and the pleasure of taking a meal, to come to God in prayer and petition. 1 Corinthians 15:58 promises to us, "Be steadfast, immovable, always abounding in the work of the Lord, knowing that your labor is not in vain in the Lord."
There are a wide variety of ways to fast. Some people fast for a full day, some take one meal and others eat only fruits and vegetables. There's really no best way to fast because what matters most is not the act but the position of the spirit and the heart.
Fasting is not about twisting God's arm
In Isaiah 58:2, God gives us His heart for true fasting: "Yet they seek me daily and delight to know my ways, as if they were a nation that did righteousness and did not forsake the judgment of their God; they ask of me righteous judgments; they delight to draw near to God. God honors the heart, not the act."
Fasting has nothing to with twisting God's arm by saying, "Lord, I met the terms you asked for. Give me what I want."
Fasting is first and foremost about delighting in drawing near to God and coming to Him with a full heart and only secondarily about approaching Him with an empty stomach.
If our motives in fasting are to get a car, some cash, a job or a relationship more quickly, we miss the point. Prayer and fasting is about receiving a greater experience of Jesus and the Holy Spirit first and being open to His miraculous move in our lives according to God's will.
There is fasting that does not work
Not all forms of fasting work. In Matthew 6:18, Jesus says, "And when you fast, do not look gloomy like the hypocrites, for they disfigure their faces that their fasting may be seen by others. Truly, I say to you, they have received their reward."
Fasting at the end of the day is first and foremost about the position of the heart before the position of a meal.
When we fast with selfish, prideful and conceited motives, God is not honoured and God cannot move in our midst. Fasting works first and foremost because we surrender to God's move in our lives and allow Him to satisfy and fill where we are empty and void. Fasting that is built on the foundation of a right heart and spirit brings us closer to God first and foremost, and fasting built on pride and selfishness return empty and void.