(All of the following is from Dallas Willard, The Great Omission)
If your neighbor is having trouble with his automobile, you might think he just got a lemon. And you might be right. But if you found out that he was supplementing his gasoline with a quart of water now and then, you would not blame the car or its maker for it running in fits and starts. You would say that the car was not built to work under the conditions imposed by the owner. And you would certainly advise him to put only the appropriate kind of fuel in the tank. After some restorative work, perhaps the car would then run fine.
We must approach current disappointments about the walk with Christ in a similar way. It too is not meant to run on just anything you may give it. If it doesn’t work at all, or only in fits and starts, that is because we do not give ourselves to it in a way that allows our lives to be taken over by it. Perhaps we have never been told what to do. We are misinformed about “our part” in eternal living. Or we have just learned the “faith and practice” of some group we have fallen in with, not that of Jesus himself. Or maybe we have heard something that is right-on with Jesus himself, but misunderstood it (a dilemma that tends to produce good Pharisees or “legalists,” which is really a hard life.) Or perhaps we thought the “Way we have heard of seemed too costly and we have tried to economize (supplying a quart of moralistic or religious “water” now and then).