Looking back at the concerns surrounding the person of Christ in the third and fourth centuries, one notices that the debates are oddly slanted in one direction. Most career heretics, such as Nestorius and Apollinaris seem to be fine with the divinity of Christ, but his full humanity was questionable. For some reason spirituality was tenable, but physicality put real a burr in their saddle. How could God– omnipotent, sovereign, and holy– mingle with the messy materiality of stuff?
I am of course, being very simplistic. It wasn't that they hated the idea of the Incarnation, but that the Incarnation is by definition a very hard thing to get one's second-order skull around. But there is still this curious trend. The divinity of Christ was taken for granted seemingly by the majority, orthodox and unorthodox alike, while His humanity was the main point of contention.
Zoom ahead to the enlightenment and one notices that the trend is reversed. Suddenly the humanity of Christ is found to be very palatable while His divinity is untenable. It became easier to conceive of Jesus as a good moral teacher than it was to believe he was God. Without going into the reasons for why Schleiermacher's offspring have such a problem with this, I will merely suggest that the locus of contemporary theology is centered on this problem, and perhaps increasingly in Evangelical circles.
How? Let's take ecology for example. The lack of Christology has been my only beef with Wendell Berry. Don't get me wrong, I love Berry and will recommend him and his organic tobacco til' the unclouded Tennessee sun goes down, but Christ is all but absent in his ecology. It is for this reason that, in spite of all of his wonderful insight that his view ultimately appears unrealistic and untenable (and his fiction a bit soapy). It can contrast a redeemed world with the fallen one, but it cannot tell us how to get from one to the other. It is in the bridge of Christ that the fallen and the redeemed are linked and the fallen is given any real hope. Douglas Moo, however, even in spite of the relatively small writing he has produced so far, finds the locus for ecology more or less in the Shema of love for God ad love for neighbor, both of which draw in a robust Christology and consequently a realistic means of caring for the earth.
Ecology is just one example, but I have begun to notice this in Feminist Theology as well and I am sure that it would be easy to find other examples. All of this goes to show that Karl Rahner was right when he said that most Christians today live as functional monotheists to whom the Trinity in all of its distinctive unity is of no consequence. So much is at stake when we neglect the daunting task of developing our theology within the framework of the persons of the Godhead, and since Christ is the most visible member, he is the easiest place to see this happen. It is imperative to insist on a robust Christology.