Reformed Protestants contend that there must be a specifically Protestant defense of all Christian doctrines. In Reformed theology the argument is that all our doctrines are interdependent. The major doctrines imply other doctrines. For example our doctrine of the atonement, will to some extent, influence our doctrine of God. Cornelius Van Til, describing the difference between a Protestant and Romanist doctrine of God, rightly says in his book A Christian Theory of Knowledge,
”The answer given is that the Protestant doctrine of God stresses his self-sufficiency and therefore his ultimate control over all that comes to pass in the course of the history of the world. The Romanist doctrine of God, while also speaking of God’s self-sufficiency, none-the-less compromises it to some extent. It does this by virtually ascribing to man a measure of self-sufficiency. And by ascribing a measure of self-sufficiency or ultimacy to man, God is in a measure made dependent upon man.”
The Protestant doctrine of God requires that it would be foundational to everything else as a principle of explanation. “If God is self-sufficient, he alone is self-explanatory.” (Van Til, 12) If God alone is self-explanatory, then he must be the final reference point in all human predication. That is to say, that God must be the final reference point in all our claims about reality and experience. God is like the sun where all lights on earth derive their power of illumination. You don’t use a candle to search for the sun. The idea of a candle, the idea of light, and fire is derived from the sun. With this understanding all creation is a derivative being made by God. It could not come into existence by chance or by itself. God is the source of everything.
When we take away the notion that God is self-explanatory or self-sufficient then we also take away the final reference point in everything that we predicate. We make God a partner with humanity and together we work to explain something we have in common, creation. Facts are then not what they are by the plan of God but they are partly that and exist by some unknown power or in and of themselves. We may look to God for the answer, because he knows better. He has more experience or he is just better at figuring this stuff our. But we would never need to make all thoughts captive to the obedience of Christ. In this view, the Christian cannot tell the non-Christian that the non-Christian view is destructive and he cannot give him any certainty to what Christianity can give him and what he needs.
The essence of the non-Christian position is that man is autonomous. It is that man is independent therefore man is the ultimate final reference point in predication. That is because the facts in the world and in creation are just there. They aren’t connected or anchored in a final point therefore man interprets reality and is in himself the basis of that reality. With this view, facts of creation come into being by “chance”. Now possibility is placed above the mind of man and above God. It has taken a place of primary and the utmost importance. Laws of logic are seen as entering the universe by happen chance, a derivative of culture or even denied.
The Christian meets the challenge of the non-Christian by exposing to them this dilemma. The best way to do this is show the non-Christian that in order for them to make statements about experience, creation or any other thing in creation they are assuming that there is an objective final reference point. They are presupposing God as they make their arguments against his existence. Christians cannot start off from an apparent objective position then move to God, just as the non-Christian cannot start off denying God unless he first affirm that God does exist.