There are mountains hidden in mountains. There are mountains hidden in hiddenness. This is complete understanding.
If we insist on visible proofs from God, we may well prepare the way for a permanent state of disappointment. True faith does not so much attempt to manipulate God to do our will as it does to position us to do his will. As I searched through the Bible for models of great faith, I was struck by how few saints experienced anything like Job's dramatic encounter with God. The rest responded to the hiddenness not by demanding that he show himself, but by going ahead and believing him though he stayed hidden.
Man cannot live without a permanent trust in something indestructible in himself, though both the indestructible element and the trust may remain permanently hidden from him. One of the ways in which this hiddenness can express itself is through faith in a personal god.