I can think of several reasons.
One is that it seems to me we’re presuming upon God when we assume He has just one thing He wants you or me to be doing next Tuesday evening. Where did we get that idea? I have to choose whether I want to write this post or stop and get some exercise. Where do I get the idea that of the two of these, one is God’s will and the other is not? What makes one good and the other not? Why can’t they both be good? After all, isn’t God capable of providing us with several good things to choose from (Genesis 2:16)? Why can’t it be that God approves of me writing this post or exercising and He leaves the decision up to me?
Furthermore, isn’t this what we do with our children? When they are very young, we hover over them and micromanage every aspect of their lives. But they will never reach maturity if we don’t adapt our style as they grow older. So we allow them to start making choices for themselves, employing the principles we have taught them. Your teenage son is trying to decide whether to work overtime at his job or go to the library to study—does anyone believe that only one of those choices is good? Does it promote maturity if we step in and make the decision for them?
Then too, it puts inordinate pressure upon the believer to think that God has a plan for every inch of their life. What clothes does He want me to wear today? What route should I take to work? What should I eat for lunch? Most important, how do I determine the answers to all these questions? How is God going to reveal it to me? I’m not suggesting the advocates of the “God has an exact plan for your life” view do this, but if they don’t, why not? How do they determine how much is God’s plan?
This view also overemphasizes God’s role on the front end of circumstances (What choice should I make?) and diminishes His presence and help throughout the entire process (Help me to honor You in this circumstance). Romans 8:28 says that God works everything together for good. It doesn’t say that everything is good (and that would certainly include some of our decisions), but that God can ultimately work it for good. In Philippians 4:12-13, Paul tells us that he had learned the secret of being content in all circumstances. Can’t we approach our decisions with that same confidence—that God can and will bless us in whatever path we choose rather than suffering paralysis from analysis because we’re convinced there is only one correct choice?
Finally, it seems like we short-circuit the Scripture when we bypass all of the instruction God gives to us through it in order to wait on Him to whisper His choice in our ear concerning every matter of daily living. Does that strike you as a good way to produce maturity? Would you think of using this method with your children?
After I’d married and left home, I’d occasionally call my father about some decision I needed to make. He would irritate me because he would listen patiently, help me outline my options, but he always refused to tell me what to do. I resented it at the time because what I wanted was a quick, easy answer—not to be stretched in terms of my personal growth. But Dad was doing what he was supposed to do as a parent. He’s been gone many years but I’m grateful that he didn’t give in and provide me with easy answers but kept pushing me to make my own decisions. Unlike my dad, our heavenly Father is not going anywhere. However, He also desires that we grow and mature and decision-making is one important component of that process.