It is perhaps helpful to understand the difference between the twin affirmations—that “Creator” is a relative name and denotes an absolute reality—as corresponding to the epistemic-noetic activity of the human knower on the one hand, and the ontological reality of God’s absolute being on the other. The difference lies not in a twofold manner of God’s existence—timeless and temporal, for example—but in the distinction between (1) the human manner of knowing and predicating about God and (2) God’s actual manner of existing.
