“To the choirmaster. A Psalm of David. The heavens declare the glory of God, and the sky above proclaims his handiwork.” (Psalms 19:1)
Natural revelation is the way in which God has made himself known to all men, without exception. As was established earlier, all men know God. This is proven as a matter of common observation. All men live and breathe and have their being in God's universe (Acts 17:28), and as such, cannot even function without acknowledging Him in some way. God's invisible attributes and eternal power are clearly seen in the created order (Romans 1:20).
Natural revelation serves two purposes. For the saint, it serves to build faith and produce an attitude of worship. Who can miss the wonder of a sunset over a watery horizon, the vastness of the universe, or the intricate design of the human body? For the nonbeliever, however, natural revelation renders men to be "without excuse", and that is essentially all that it does. Man, in his fallen state, is unable to acquire sufficient knowledge of God unto salvation through natural revelation.
The metaphysical conflicts between the Christian and the non-Christian worldviews begin with this fundamental disagreement concerning man's natural state. Regardless of what version of unbelief one may adopt, it will be based on the assumption that the human mind is autonomous, that it can function outside the creative attributes and providence of God, and that man is basically OK in his current condition. The Christian, on the other hand, sees man as a fallen creature, and sees the world, his mind, and everything that exists as being totally dependent on God. This has obvious bearings upon how science is approached, as well as how one deals with "evidence". The fact that science itself is dependent on God's natural revelation cannot be dismissed, and thus the approach to science will be contingent upon one's metaphysical worldview.
Unfortunately, the naturalistic worldview has become the default for many scientists today, even for those who profess Christ. God is often seen as another hypothesis by which our infallible minds may or may not justify. Indeed, there is something attractive about using "scientific apologetics" to defend the faith. Just a cursory glance at the natural world shows overwhelming evidence for design. Consider the impressive display of order in the human body, the solar system, the cell, etc.
As obvious as this is without even digging into science, it becomes even more impressive when we do. There is an astounding amount of scientific evidence that the universe that we live in was purposed for human life. Physicists refer to this as The Strong Anthropic Principle. Volumes of material have been written, and continue to be written, on the amazing precision to which so many properties of our universe have been fined tuned, such that even the minutest deviation in any of these properties would make the universe uninhabitable for life as we know it. (See "Design And The Anthropic Principle").
“Scientists are slowly waking up to an inconvenient truth - the universe looks suspiciously like a fix. The issue concerns the very laws of nature themselves. For 40 years, physicists and cosmologists have been quietly collecting examples of all too convenient "coincidences" and special features in the underlying laws of the universe that seem to be necessary in order for life, and hence conscious beings, to exist. Change any one of them and the consequences would be lethal. Fred Hoyle, the distinguished cosmologist, once said it was as if "a super-intellect has monkeyed with physics". - physicist Paul Davies (cited in David Berlinski’s The Devil’s Delusion).
As impressive as this evidence is, it is a mistake to assume that unbelief is the result of a lack of information about the natural world. In fact, the unbeliever has the same evidence for God as the believer has. Per Romans 1:18, the unbeliever suppresses the truth, not in ignorance, but in unrighteousness. His problem is not intellectual, it is ethical. In rebellion against God, the unbeliever has adopted a position of intellectual autonomy, and needs to acquire a new way of thinking, subjecting himself to the commandment to love God with his mind (Luke10:27) through the regenerating power of the Holy Spirit. In short, science, particularly in a materialistic worldview, cannot provide any useful knowledge of God unto salvation.
This is due to the fact that natural revelation has built in limitations when it comes to persuading fallen men. Well meaning scientific apologists often fail to understand the supernatural basis for salvation. Unbelievers already know God through natural revelation (Romans 1:18-22), and yet do not have a knowledge of God sufficient for conversion (1 Corinthians 2:14). By adopting a naturalistic worldview, the evidential apologist implicitly denies the Lordship of Christ over the human mind. This approach is disobedient to God's commandment for apologists to "in your hearts honor Christ the Lord as holy" (1 Peter 3:15), even if one were to somehow vindicate God in the process. The man-made construct of "science" simply has no authority to rule on the subject of God.
Finally, appealing to "science" in order to prove God’s existence to the unbeliever results in the inability to prove anything. Instead, we are left with what unbelievers refer to as the“God of the Gaps” fallacy – ie., using God as a stop gap for what we otherwise cannot explain given strict materialistic presuppositions. Dietrich Bonheoffer pointed out the biggest problem with the “God of the Gaps” approach to apologetics:
"...how wrong it is to use God as a stop-gap for the incompleteness of our knowledge. If in fact the frontiers of knowledge are being pushed further and further back (and that is bound to be the case), then God is being pushed back with them, and is therefore continually in retreat. We are to find God in what we know, not in what we don't know.“ (Dietrich Bonheoffer - Letters and papers from Prison 1997, p. 311)
What then, is the correct approach to the scientifically literate unbeliever? Instead of trying to justify God via science, we need to point out that science cannot be justified apart from God, who is the ultimate standard of truth and knowledge.