Evidently, then, our first priority in trying to understand Van Til’s metaphysics of knowledge is to explore his doctrine of God. On the first page of his Introduction to Systematic Theology, he says, “Fundamental to everything orthodox is the presupposition of the antecedent self-existence of God and his infallible revelation of himself to man in the Bible”.
“Self-existence,” sometimes called aseity, refers to the fact “that God is in no sense correlative to or dependent upon anything besides his own being. God is the source of his own being, or rather the term source cannot be applied to God. God is absolute. He is sufficient unto himself.” Often Van Til summarizes this concept by referring to the “self-contained God.”
He quotes favorably a passage from Bavinck to the effect that all of the other virtues of God are included in his aseity. Thus, when Van Til goes on to discuss God’s immutability, he bases that doctrine on the divine aseity: “Naturally God does not and cannot change since there is nothing besides his own eternal Being upon which he depends (Mal 3:6; James 1:7).” Since God’s immutability is based upon his “self-contained fullness,” it is quite opposite to the immutability of Aristotle’s unmoved mover, an abstract thought [which is] thinking itself.
Notice how [Van Til] moves here from “self-contained” to “self-contained fullness.” That is important…
(From John Frame, “Cornelius Van Til: An Analysis of His Thought”, Phillipsburg, NJ: Presbyterian and Reformed Publishing, ©1995, pgs 53-54.)
Reading this, I was struck by the comparative use of the term “fullness” by Rome. Rome says it has “the fullness of the faith”.
Consider that term in juxtaposition with another account of what can be called the “self-contained fullness of God”. Here is the account by Scott Oliphint:
The first thing that is necessary to grasp about the attributes, properties, or perfections (which I use as synonyms) of God, therefore, is that a basic distinction must be made between God as he is and exists in himself and God as he condescends. The theological (i.e. biblical) reason for this distinction is that it is obvious that before anything was created, there was and has always been God. That is, God himself is not essentially subject to time; he does not, according to his essential character, live, move, and have his being in a temporal context. He has no beginning and will have no end. Not only so, but before there was anything created, there was only God. It is not as though things existed—ideas, concepts, properties, and so forth-alongside God prior to creation. Before creation, there was nothing but God. To put it more starkly, before God created, there was not even nothing. There was God and only God.
(K. Scott Oliphint, “God With Us: Divine Condescension and the Attributes of God”, Wheaton IL: Crossway, 2012, from the Introduction, pg 13.)
Consider, for a moment, “the self-contained fullness of God”, compared with what Rome calls “the fullness of the faith”. Let that thought sink in for a few moments.