Doubt is part of the faith-net. We are all Thomas-like, at some level yearning to be able to put our mental fingers on Christ's wounds to "know" that he is really in our lives. For us "moderns" - post scientific revolution - the challenge of doubt is even greater since all things spiritual have to do battle with the mindset that what we can "know" is all that really matters. We cannot "know" anything about God or about Jesus - or Moses or Muhammad - or anyone. We live in a world where we do know experientially that we cannot completely rely on any human account of events in the past, even things just a few days ago. And the advances of science, the amazing achievements that have flowed from human efforts to understand and find the laws that govern the physical world are awe inspiring.
My faith in God is not based on what I can know. It is based in all honesty on internal commitments or "leaps of faith" that my mind, heart and soul have made to experiences in my life that seem somehow more real to me than anything I have ever learned: a sense that there was some "being" with "eyes on my soul" that I swore an oath of integrity to when I was still a child, that there was a power that surrounded me that felt like encouraging love, a pillar of faithfulness to me that I could never really doubt in any deep sense of that word. I doubted intellectually, because I could not ever find arguments that could serve as "proof" that Jesus even existed historically in exactly to detail set forth in the gospels. But he was there in me, in some place deeper than my mind, when I was suffering great stress and went through a hypnotism session with a doctor that led me straight to Jesus' face and this was during a period of some fifteen years when I would have told you I was an atheist. And I remember also thinking during that time that God - if there was a God - would rather have me be honest about my inability to believe than pretend that I was a believer. Such irony!
Modernists need to consider that there might be a level of "reality" that is beyond the scope of our scientific inquiry. It is a level in us on which we build our lives, construct our values and make commitments that give what we call meaning or purpose to our lives.