Do you have enough evidence to believe?
You'll never get all the evidence there is to get. You'll always have some questions. You may always harbor some doubts. But do you have enough?
Faith ... the kind of faith that the Bible talks about ... isn't always a blind faith. Philosophers write about leaps of faith. Biblical authors talk about going with what you know. Or, better yet, who you know.
I was talking with a friend today about that scene in Mark 4 when Jesus calms the storm. Right after he commands the wind and the waves "Be still" and the storm runs away, Jesus turns to his disciples and asks "Do you still have no faith?" As my friend and I talked about the passage, it became clear that the "still" in "Do you still have no faith?" is and important "still."
Jesus' disciples had seen him work miracles and cast out demons. These disciples had heard Jesus teach and had shared life with him. They had heaps of evidence. When Jesus pokes at them for their unbelief, he's poking them because they ignored the evidence.
You may have a heap of doubts, a heap of questions. But you may also have a heap of evidence. At some point, you'll have to ask whether or not you have enough evidence to believe.
And then you'll have to ask whether you want to believe. That's much more difficult.