The simple fact is, our actions reveal what we really believe. We can say we believe something, hope we believe something, want to believe something, pray to believe something, etc., but we don’t really, truly believe it until our actions prove that we do.
I believe that the ground is solid and that when I step on it, the law of gravity will keep me from flying into space. I don’t have to rationalize it or analyze it or reflect on it logically. I step on the ground without even thinking about it because I believe so strongly in its strength. That is the way the renewing of the mind works. God transforms the deepest part of our hearts by His Spirit and His truth, and pretty soon we don’t have to try so hard to live the way we think He wants us to, because it just happens naturally, like stepping on solid ground.