Doubt

“Christianity places a premium on the absolute truthfulness and trustworthiness of God, so understanding doubt is extremely important to a Christian. Of course, faith is much more than the absence of doubt, but to understand doubt is to have a key to a quiet heart and a quiet mind. Anyone who believes anything will automatically know something about doubt. But the person who knows why he believes is also in a position to discover why he doubts. The Christian should be such a person. Not only does a Christian believe, he is a person who ‘thinks in believing and believes in thinking,’ as Augustine expressed it. The world of Christian faith is not a fairy-tale, make-believe world, question-free and problem-proof, but a world where doubt is never far from faith's shoulder. Consequently, a healthy understanding of doubt should go hand in hand with a healthy understanding of faith. We ourselves are called in question if we have no answer to doubt. If we constantly doubt what we believe and always believe-yet-doubt, we will be in danger of undermining our personal integrity, if not our stability. But if ours is an examined faith, we should be unafraid to doubt. If doubt is eventually justified, we were believing what clearly was not worth believing. But if doubt is answered, our faith has grown stronger still. It knows God more certainly and it can enjoy God more deeply.” (pp. 15-16).
“Problems strike us all differently. What is trivial to one person may raise titanic questions for someone else. Some people face doubt only if they find no answer; others trigger doubts merely by raising questions. What puzzles a philosopher and taxes his mind to distraction may look completely irrelevant or quite obvious to a businessman. The point is not to judge who is right, but to meet and resolve whatever doubt is a problem to a particular person” (p. 32).No matter what level of doubt we face, living in constant doubt is not where we want to live our lives. But neither should be automatically feel guilty and sinful for all doubting thoughts. The reality is that doubt is inevitable in the Christian life. Guinness writes, “In the same way assurance of faith depends on our grasp of God and his faithfulness and not on a mastery of all the doubts that are ever likely to assail us. Otherwise faith could never be assured while one last doubt remained” (p. 33).
“What is more, faith, like health, is best maintained by growth, nourishment and exercise and not by fighting sickness. Sickness may be the absence of health, but health is more than the absence of sickness, so prevention is better than cure. Equally, faith grows and flourishes when it is well nourished and exercised, so the best way to resist doubt is to build up faith rather than simply to fight against doubt” (pp. 33-34).
In Two Minds: The Dilemma of Doubt and How to Resolve It by Os Guinness
http://www.sovereigngraceministries.org/Blog/category/Doubt.aspx