Trust like this is an affront to reason, the control our egos crave. Which is precisely the point. Trust does not work because we have captured God in our minds. It works regardless of the fact that, at the end of the day, we finally learn that we can’t.
The focus moves from ourselves to God, in whom we trust—what Jesus calls “dying” and “losing” our lives.
The need for certainty is sin because it works off of fear and limits God to our mental images. And God does not like being boxed in. By definition, God can’t be. I believe we are prone to forget that.
We are told that, in response to this promise, Abraham “believed the LORD” (Genesis 15: 6)—which is the first place in the Bible where believing comes up. Believe in the original Hebrew of this story is ‘aman (ah-MAHN), which has made its way into English, and we all know it as amen—only, it’s not a social cue that we’re done praying, and it’s okay to open our eyes and dig in. Amen as the final word of a prayer is a declaration of trust: “We’re done talking now, Lord. We’ve said our peace and put this matter into your hands. Now we trust you with it.”