Faith is a lot like that. We harness up and believe fully, at least as far as logic goes, that our "cord" is going to hold. Yet there is that moment when we hesitate at the top of a 40 foot---or maybe 4,000 foot---structure, because logic goes against jumping.
The hardest part is letting go, because when we do that we relinquish all control. We have to give ourselves over to the One Who is holding us.
Then comes the moment when we do fall and it seems like God is making a game of us as we bounce back and forth. Life does that. But when it comes down to the very end, we can all, without fail, say, "Faith is a free fall, but the anchor holds, I made it through intact, and my life is richer for having experienced the leap of faith."