God does not normally reveal Himself in a way that our physical senses can perceive Him, so this is why faith is required on our part. Now I’m not suggesting that God doesn’t allow us to be aware of His presence; He does. Our experience of Him, however, comes by spiritual means—not physical. But why would God keep Himself hidden at all? Wouldn’t it be much easier to simply appear to us periodically to tell us what He wants? Well, that wouldn’t require faith, would it? Our inability to grasp Him by our natural senses makes faith indispensable. Faith is at the very heart of God’s plan for us. That’s why Scripture tells us that it’s impossible for man to satisfy God without it. But since faith is so contrary to everything instinctive to our humanity, believing Him will never be all that easy. To be sure, it appears that He never meant it to be!
(Excerpted from “Free from the Power of Sin: The Keys to Growing in God in Spite of Yourself”)