Emil Brunner and Karl Barth famously had a serious quarrel, even fall-out, over Barth’s perception of ‘natural theology’ in Brunner’s approach. While it is true that Brunner affirmed something like Calvin’s sensus divinitatis, he also has some very strong points of convergence with both Barth and Thomas Torrance for that matter. I’m inclined to go with Barth on all things contra-natural theology, but I actually think Brunner is much closer to Barth than say even Calvin or any of the Post Reformed orthodox in the 16th and 17th centuries. Note what Brunner writes, if I hadn’t told you beforehand you might have thought this was Barth instead (well maybe):
(2) Secondly, the concept, the “Name” of God, suggests further that God is Person: He is not an “IT”; He is our primary “Thou”. That which we can think and know by our own efforts is always an object of thought and knowledge, some thing which has been thought, some thing which has been known, therefore it is never “Person”. Even the human person is never truly “person” to us so long as we merely “think” it; the human being only becomes “person” to us when he speaks to us himself, when he manifests the mystery of his being as a “thou”, in the very act of addressing us.
Let’s stop here for just a moment before we pick up again. In some ways this functional understanding of what constitutes personhood is problematic; not just for reasons that implicate say the ethics of something like abortion and establishing personhood, but also because Brunner is using this as an analogue, a social analogue for determining the personhood of God (someone might want to call this a type of analogia entis or ‘analogy of being’). That notwithstanding, what he writes following still is insightful; Brunner continues:
It is true of course, that to a certain extent we can know the human “thou” by our own efforts, because, and in so far as it is “also an I”, a fellow-human being. The mystery of human personality is not absolute; it is only relative, because it is not only “other than I” but “the same as I”. It can be placed under the same general heading “Man” along with me; it is not and unconditioned “Thou” because it is at the same time a “co-I”. There is no general heading for God. God in particular has no “I” alongside of Himself. He is the “Thou” which is absolutely over against everything else, the “Thou” who cannot at the same time be on the same level with “me”, “over-against” whom He stands.
Therefore I cannot myself unconditionally think God as this unconditioned “Thou”, but I can only know Him in so far as He Himself, by His own action, makes Himself known to me. It is, of course, true that man can think out a God for himself—the history of philosophy makes this quite plain. In extreme cases a man can “think” a personal God; theistic philosophy is a genuine, even if an extreme possibility. But this personal God who has been conceived by man remains some-thing which has been thought, the object of our thought-world, acting, speaking, manifesting Himself—He does not meet me as a “Thou”, and is therefore not a real “Thou”. He is, as something which I have thought, my function, my positing: He is not the One who addresses me, and in this “address” reveals Himself to me as the One who is quite independent of me.
The God who is merely thought to be personal is not truly personal; the “Living God” who enters my sphere of thought and experience from beyond my thought, in the act of making Himself known to me, by Himself naming His Name—He alone is truly personal.
Karl Barth in his Göttingen Dogmatics has a whole chapter entitled Deus dixit, ‘God has spoken.’ This is language that Barth appropriated from Dutch Reformed theologian Herman Bavinck, and now we see it as a theme in Brunner’s theology as well. The social analogy notwithstanding, the important aspect to highlight here is that for the Christian we don’t think up God, we don’t think a God concept, we instead are confronted by the living voice of God revealed in Jesus Christ; and it is here where our conception of God comes from.
So what’s the “practical” implication of this? I would say that, if Brunner et al. is right, Christians are dependent upon revelation in order to think God. We are dependent upon hearing his voice through the voice of the eternal Son incarnate in Jesus Christ. This means, I would contend, that Christian theologians should not try to discover a concept of God as a prius to the God revealed; we should not attempt to synthesize the god discovered by the philosopohers with the God revealed in Jesus Christ. At most, as the patristic theologians did, we might be able to ‘evangelize a metaphysic’ and use the grammar present therein in order to help us talk about God; but only with the qualification that said metaphysic has been retexted in a non-correlationist way under the pressure of the triune God revealed in Christ.
That didn’t sound very practical, did it? Practically speaking I think Christians should not be afraid of the so called ‘scandal of particularity.’ We serve a peculiar and particular God, he is sui generis, unique, and special. He is only knowable because he graciously wanted to be known, and so he became us in Christ that we might become him (so says Irenaneus). The Gospel is the power of God, as such we shouldn’t be afraid to speak after and from this particular God revealed in Jesus Christ. The world may not like it, other Christians might not even like it, but we must insist that the God we speak of and to is the One who first spoke to us in his Son.
 Emil Brunner, The Christian Doctrine of God (Philadelphia: The Westminster Press, 1949), 121-22.
 Ibid., 121-22.