The argument for the existence of God and for the truth of Christianity is objectively valid. We should not tone down the validity of this argument to the probability level. The argument may be poorly stated, and may never be adequately stated. But in itself the argument is absolutely sound. Christianity is the only reasonable position to hold. It is not merely as reasonable as other positions, or a bit more reasonable than other positions; it alone is the natural and reasonable position for man to take. By stating the argument as clearly as we can, we may be the agents of the Spirit in pressing the claims of God upon men. If we drop to the level of the merely probable truthfulness of Christian theism, we, to that extent, lower the claims of God upon men. This is, we believe, the sense of Calvin’s Institutes on the matter.
– Cornelius Van Til, Common Grace and the Gospel p.77