I view fasting the same way I view prayer and since Pink and Gill have said it better than I could ever hope I'll quote them. (Just substitute fasting for prayer and you'll get the gist.)
A. W. Pink, “…what is now being taught on the subject of prayer, and the deplorable thing is that scarcely a voice is lifted in protest. To say that “human destinies may be changed and moulded by the will of man” is rank infidelity—that is the only proper term for it. Should any one challenge this classification, we would ask them whether they can find an infidel anywhere who would dissent from such a statement, and we are confident that such an one could not be found. To say that “God has ordained that human destinies may be changed and moulded by the will of man”, is absolutely untrue. “Human destiny” is settled not by “the will of man,” but by the will of God. That which determines human destiny is whether or not a man has been born again, for it is written, “Except a man be born again he cannot see the kingdom of God”. And as to whose will, whether God’s or man’s, is responsible for the new birth is settled, unequivocally, by John 1:13—”Which were born, not of blood, nor of the will of the flesh, nor of the will of man, but OF GOD”. To say that “human destiny” may be changed by the will of man, is to make the creature’s will supreme, and that is, virtually, to dethrone God. But what saith the Scriptures? Let the Book answer: “The Lord killeth, and maketh alive: He bringeth down to the grave, and bringeth up. The Lord maketh poor, and maketh rich: He bringeth low, and lifteth up. He raiseth up the poor out of the dust, and lifteth up the beggar from the dunghill, to set them among princes, and to make them inherit the throne of glory” (1 Sam. 2:6-8).
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John Gill provides a proper theological background to prayer, “…it should be said that God’s will is immutable, and cannot be altered by our crying. When the mind of God is not toward a people to do them good, it cannot be turned to them by the most fervent and importunate prayers of those who have the greatest interest in Him—”Then said the Lord unto me, Though Moses and Samuel stood before Me,
yet My mind could not be toward this people: cast them out of My sight, and let them go forth” (Jer. 15:1). The prayers of Moses to enter the promised land is a parallel case.
Our views respecting prayer need to be revised and brought into harmony with the teaching of Scripture on the subject. The prevailing idea seems to be, that I come to God and
ask Him for something that I want, and that I
expect Him to give me that which I have asked. But this is a most dishonoring and degrading conception. The popular belief reduces God to a servant,
our servant: doing our bidding, performing our pleasure, granting our desires. No; prayer is a coming to God, telling Him my
need, committing my way unto the Lord, and leaving Him to deal with it as seemeth
Him best.
This makes my will subject to His, instead of, as in the former case, seeking to bring His will into subjection to mine. No prayer is pleasing to God unless the spirit actuating it is, “
not my will, but thine be done”.
“When God bestows blessings on a praying people, it is not for the sake of their prayers, as if He was inclined and turned by them; but it is for His own sake, and of His own sovereign will and pleasure. Should it be said, to what purpose then is prayer? it is answered, This is the way and means God has appointed, for the communication of the blessing of His goodness to His people. For though He has purposed, provided, and promised them, yet He will be sought unto, to give them, and it is a duty and privilege to ask. When they are blessed with a spirit of prayer, it forebodes well, and looks as if God intended to bestow the good things asked, which should be asked always with submission to the will of God, saying,
Not my will but Thine be done”
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As you can see prayer and fasting are meant to bring us into subjection to the will of God. It's a dying of self to the creator who is Sovereign over all, who is to be trusted and loved. We are to accept Christ's will, renew our minds to the revealed will of God in the scriptures by seeking to think God's thoughts after him. Does this mean we shouldn't pray or fast? Of course not. It simply means that God is Lord of Lords, King of Kings and to be given our faith and trust in humble thanksgiving.
Amen.
j