Coming now to the knowledge that man in paradise would have of God, we must notice first of all that there man would be able to reason correctly from nature to nature’s God. But the meaning of this fact should be taken in connection with what we have said when discussing the true theistic conception of physics. We may perhaps best bring out what we mean by saying that man could originally reason from nature to nature’s God by contrasting it to what has usually been meant by that statement. In the first place, when men say that we can reason from nature to nature’s God, they usually take for granted that nature as it exists today is normal, and that the human mind which contemplates it is normal. This is not true. Nature has had a veil cast over it on account of the sin of man, and the mind of man itself has been corrupted by sin. Accordingly, we must not, now that sin has entered into the world, separate natural theology from theological psychology. After sin has entered the world, no one of himself knows nature aright, and no one knows the soul of man aright. How then could man reason from nature to nature’s God and get anything but a distorted notion of God? The sort of natural theology that the sinner, who does not recognize himself as a sinner, makes is portrayed to us in the first chapter of Romans.
– Cornelius Van Til, An Introduction to Systematic Theology p.133