Most people have the wrong impression here. For example, people fast as an act of law, to make God do something. Typically, it goes like this: They pray and nothing happens. Then they think, “I don’t know why the Lord hasn’t heard my prayer, but I’ve prayed and nothing’s happened yet.” Then they go to church and get somebody to agree with them. Still nothing happens. So they say, “If all else fails, I’ll go on a fast until I get my answer.” What they’re saying is, “I don’t know why God hasn’t answered my prayer, but He’ll answer it when I get into a fast. In other words, a fast becomes a lever or a pry bar on God. People think, “I don’t know why God is not budging, but this’ll do it. Fasting will get Him. When He sees me about to waste away, I know that regardless of how upset He is with me, He’ll have mercy. Surely He’ll move on my behalf when I’m about to die.” We play on God’s sympathy.
That kind of fasting will get you nothing but hungry. It does not accomplish a thing. Fasting doesn’t give you any more “pull” with God — He doesn’t love you a bit more if you fast or don’t fast, or if you pray or don’t pray. If you never fasted or prayed again, God’s love toward you would still be the same. He doesn’t change. God doesn’t keep a chart with the hours you’ve spent praying and fasting and then, when you reach a certain level, He assigns you “priority mail” and has to answer your prayer!
God doesn’t operate that way. You don’t influence His attitude or actions toward you through your acts. God loves you because He is love. Prayer and fasting don’t move Him.
But prayer and fasting does move you. Suppose your senses dominate you to the point that when God’s Word says “By whose stripes ye were healed” (1 Pet. 2:24), your body rebels and says, “No, I’m not healed. I hurt.” How are you going to get that body to submit itself to greater spiritual truth?
Some of us are totally dominated by our bodies. Our bodies say, “Eat!” and we say, “How much?” We do whatever it tells us to. Most of us can look in the mirror and see more than enough evidence that we’re not doing well in this area (there are some skinny gluttons out there, too). If your body has dominated you, if you indulge your flesh, remember what Hebrews 5:14 says — that by reason of use we have our senses exercised to discern both good and evil.
You’ve got to exercise your senses. It’s by reason of use.