A neat statement from Barth regarding the Triune root of creation and revelation: “the intradivine possibility in virtue of which God can be manifest to us as the Creator and as our Father is not a self-grounded and self-reposing possibility.  It rather presupposes a possibility of this kind and it presupposes an event in God in virtue of which it is posited as a possibility.  It arises out of a self-grounded and self-reposing possibility in God.”

Specifically, this is rooted in the fact that the God the Father “repeats” as God the Son: “This, the original, the source, knowledge and will in God from which proceeds the second thing, the the copy, issue, word and decision, in short, the fact that as the Creator and as our Father He can set Himself in relation to everything distinct from Him - this first thing in God Himself is the eternal Father in the sense of the doctrine of the Trinity.  God is the eternal Father inasmuch as from eternity and in eternity He is the Father of the Son who from eternity and in eternity participates in the same essence with Him.  In this relation and not in any other way God is God - the God who reveals Himself in the Son as the Creator and as our Father.”