The function of faith is not to reduce mystery to rational clarity, but to integrate the unknown and the known together in a living whole, in which we are more and more able to transcend the limitations of our external self.
When you set off on the path, the first thing you do is surrender yourself to a greater power, for you will encounter things you will not understand. You will understand things only with your heart, and that can be a little frightening. For a long time, the journey will seem like a Dark Night, but then any search is an act of faith. But God, who is far harder to understand than a Dark Night, appreciates our act of faith and takes our hand and guides us through the Mystery.