"Faith requires that a man be out over the deep, over seventy thousand fathoms. The attempt to take away this uncertainty is an attempt to do away with faith."
I find this very insightful. Faith without uncertainty is not faith but knowledge. In this life we must stride forth based on our faith in Jesus and his promises toward us. We do not have the luxury of only doing things for Jesus that we know will turn out well. At certain points in my life I have been tempted to not do difficult things (like give generously) because these things leave me with uncertainty about the future. The reality of life is that a faithful life to Jesus always leads us into uncertainty, because that is the nature of faith. If our faith in Jesus does not lead us into uncertainty is probably a sign that we are living more by human wisdom than divine wisdom. When our faith as Christians leads us into uncertain waters is a sign that we are following Jesus.