I hear you on this, too. I think about my own life and how I've seen some amazing things that I believe can only be explained by God's grace and intervention on my behalf. Even so, I find myself doubting his existence or power from time to time. I like to think that I would have stayed true, but I know myself well enough to suspect that I might have given into the temptation for money, despite what I'd seen. Also, don't forget that while Judas was the only one to actively betray Jesus, all of the disciples deserted him when he was arrested. The Bible also tells us that the same people who had seen God part the Red Sea didn't have faith to believe God would allow them to conquer the Promised Land. Sometimes our fears overrule our experience.