In its strictest sense, human reason will never acknowledge the existence of God. It will explain away all actions and things according to that which can be scientifically measured. It is only when a person's reasoning allows him to grasp the idea that the greater realities of life (such as love) surpass human measurement that he will consider the existence of God. It is then that he can begin to make the distinction between divine knowledge and natural knowledge.
But the wisdom that is from above is first pure, then peaceable, gentle, and easy to be intreated, full of mercy and good fruits, without partiality, and without hypocrisy. James 3:17
A continued quest to understand the greater realities of life will reveal to the searcher that natural knowledge can be analyzed whereas spiritual knowledge is ascertained. His discovery will be that it is only by studying divine knowledge that one can gain spiritual understanding and thus appreciate the perfection of God, the perfection of Jesus Christ, and the perfection of God’s words as originally inspired in the Holy Bible. His journey will culminate in a detailed study of the perfection of God's Word.
Study to shew thyself approved unto God, a workman that needeth not to be ashamed, rightly dividing the word of truth. II Timothy 2:15