When I was in the hospital, I received many cards. Among them was one that had an actual mustard seed in a little container pasted on the front of it along with the words, "For if you had faith even as small as a tiny mustard seed you could say to this mountain, ‘Move!’ and it would go away. Nothing would be impossible." A mustard seed is really no big deal. But from this small seed grows a very large plant in a very short period of time.
Using a tiny mustard seed, Jesus suggests a very remarkable thing. He says that if our faith is only as large as this very small seed, we can do great things, as great as moving a mountain from one location to another. In fact, he says, "Nothing would be impossible for us." As Jesus talks to us about a mountain-moving faith, some of us possess a mountain of doubt.
It has been my experience that those who doubt more than they believe try to subject God to the limits of their own reason. They want God on their terms, according to their own rationale. They seem to say that if they were God, things would have been done differently. And right here, I believe, is the crux of the problem. They see themselves as God. For to be wiser than God is to be God.
If we really want to get to know God, it is better to begin with faith. What we really need is a faith that seeks understanding rather than an understanding that seeks faith. To put it another way, "In Doubt? Faith It!" No matter how little our faith might be - even if it is smaller than a mustard seed - God is saying to us today that there is great potential for its growth.