The fact is, as humans we do doubt. When God seems silent or absent, we can't help but wonder. We grieve. We can't make sense of why things are happening the way that they are. The Bible doesn't offer easy answers, either. It is full of promises of God's provision for those who have faith and believe against all odds, yet it is also filled with stories of men and women who followed God in obedience and suffered terribly. It is full of mighty victories as well as people who died not having received their promised inheritance.
Even worse, we Westerners have let consumerism creep into our Christianity. We "pay" God with our acts of obedience and faith, and then expect God to "provide" our material needs. I'm not sure that's a biblically accurate faith, however.
What if God never met your needs? What if He didn't answer your prayers in the way that you thought He should? In other words, what if there's nothing in it for you? Is God still God? Is He still worthy of honour? If your faith is only about how it benefits you, then God is not at the centre of your world; you are. God exists to serve you and not the other way around. Yet to have a faith with no element of selfishness - no ulterior motives - is difficult at best.
The tension that exists between doubt and faith is troublesome to handle. There are no easy answers, no platitudes, no soft berths. To castigate those who have doubts is to deny the example of Jesus, who was kind and compassionate with those who struggled. In fact, the only people that Jesus castigated were the religious experts - the ones with all the answers.