All knowledge of God rests on revelation. Though we can never know God in the full richness of his being, he is known to all people through his revelation in creation, the theater of his glory. The world is never godless. In the end there are no atheists; there is only argument about the nature of God. The recognition is universal of a power greater than human beings themselves, to whom they owe piety.
Reformed Dogmatics Vol. 2: God and Creation (Grand Rapids, Michigan; Baker Academic; 2004) p. 53.