Revival preacher, A.W. Tozer, wrote, "To most people God is an inference, not a reality. He is a deduction from evidence which they consider adequate but He remains personally unknown to the individual...For millions of Christians, God is no more real than He is to the non-Christian."
Tozer further wrote, "What do I mean by reality? I mean that which has existence apart from any idea any mind may have of it, and which would exist if there were no mind anywhere to entertain a thought of it."
The world is full of smart people who have tried to deny God with their reason and mind. But their words still require faith. The question is who do you have more faith in - the words of men or God. People point to the physical world as if it is superior to the spiritual world. But all physical things first came from that which is spirit because God is a spirit.
It can be real easy to push the "other world" into the future. But as Tozer wrote, "The spiritual world is not future, but present. It parallels our familiar physical world, and the doors between the two worlds are open."
So I guess we come back to the initial question. What is real? And the answer is quite simple. Reality consists of more than you can see with the senses or prove beyond a doubt in your mind. The fullness of reality can only be realized through the eyes of faith in God and His Word.
