This sentence and the sentence above it is one of the most profound pieces I've seen about theology. I think it's lurking unspoken in the writing of Jenson and perhaps Barth. It means that the object of theology is not just the entity of God, nor is it merely the human experience of God and faith. It's about explaining the content of the relation of humans to God, and God to humans. And, once this is thought about, one comes to realize that theology could not be anything else. It could not be about God as God, because theology uses language and human reason, which necessarily implies some set of assumptions about the relationship between God and humans. It implies that God is something that can be spoken of by humans, that he can be accurately discussed. The very fact that we speak about him at all means that God is the sort of thing that Humans can in some way understand. This is the case even if one tries to speak apophatically, because then one delimits the being of God by defining what he isn't, and that necessarily implies something positive about his reality. So, theology is necessarily about explaining how exactly God relates to human beings, and this is the most basic and visceral object of theology. It is what comes before any talk about God as God, and it is what comes before any talk about humans as humans.
Thus, the issue for Christians will quickly become, what is the nature of the relationship between God and humans? Is it the Triune God as Jenson would be inclined to say, or is Christ, as Barth would want to say?
Also, this is x/ne because I didn't see that he was saying that this is NOT the object of Theology.