"It is exceedingly dangerous to confuse the orthodox concept of the incomprehensibility of God with the ultimate mysteriousness of the universe as held by modern thought. Modern thought in general, and modern logic in particular, holds . . . that God is, at most, an aspect of Reality as a whole. Hence, God is himself surrounded by darkness or mystery, just as man is surrounded by darkness or mystery. In other words, modern thought believes in an ultimate irrationalism, while Christianity believes in an ultimate rationality. It is difficult to think of two types of thought that are more radically opposed to one another. It is the most fundamental antithesis conceivable in the field of knowledge. . . . The very foundation of all Christian theology is removed if the concept of the ultimate rationality of God be given up."-- Cornelius Van Til, An Introduction to Systematic Theology, (Phillipsburg, NJ: Presbyterian and Reformed Publishing, 1995), p. 13
I am just starting Bahnsen's Van Til's Apologetic - looks to be very edifying.