We have already indicated that the best apologetic defense will invariably be made by him who knows the system of truth of Scripture best. The fight between Christianity and non-Christianity is, in modern times, no piece-meal affair. It is the life and death struggle between two mutually opposed life and world-views. The non-Christian attack often comes to us on matters of historical, or other, detail. It comes to us in the form of objections to certain teachings of Scripture, say, with respect to creation, etc. It may seem to be simply a matter of asking what the facts have been. Back of this detailed attack, however, is the constant assumption of the non-Christian metaphysics of the correlativity of God and man. He who has not been trained in systematic theology will often be at a loss as to how to meet these attacks. He may be quite proficient in warding off the attack as far as details are concerned, but he will forever have to be afraid of new attacks as long as he has never removed the foundation from the enemy’s position.
– Cornelius Van Til, An Introduction to Systematic Theology p.23-24