In Hammann's biography of Rudolf Bultmann there's an interesting spat (exchange?) between Barth and Bultmann about what preaching is and what it is for. Bultmann had submitted two sermons to Barth for inclusion in the journal Barth was editing, Theological Existence Today. Barth declined to publish them. His reason? In Bultmann's sermons he saw "not really Christ preached, but rather...the believing person made explicit."
Bultmann wasn't surprised his sermons were rejected, and wrote to Barth:
"When you ask questions of the text, it is according to a dogmatic recipe; the text does not speak with its own voice. After a few sentences, one already knows everything that you will say and only asks oneself now and again how he is going to get that out of the words of the text that follow...this exegesis doesn't grip me; the text does not address me; rather, the blanket of dogmatics is spread out over it." Bultmann proposed that the goal of preaching is "that under the auspices of the word, the listener's existence is made transparent to him." (HammannPage 337)
I guess we are overhearing a debate about the importance of doctrinal preaching over against the relevance of contextual preaching. But that's too simple and does justice to neither preacher. Both are theologians whose faith commitment remained central to all their work; both are preachers whose goal was to be the medium of God's address to the congregation. Barth would not deny the dogmatic control exerted in exegesis, but I think would argue that dogmatic control was rooted in and grows out of faithfulness to the text itself. Likewise Bultmann would not argue that preaching should explicitly address the context and experience and existence of the congregation, but any reading of his sermons makes clear Christ is indeed preached; but not as dogmatic theology. Barth was right to trace this clear division of opinion, and difference in style and content, to how each saw the relationship between Christology and Anthropology. It is interesting that Barth's quarrel with Brunner can be summed up in almost exactly the same terms and concerns.
Bultmann and Brunner were deeply engaged in the relations of gospel and culture. Barth's project was altogether less interested in cultural context and human existence as such; his starting point was the dogmatic core of Christian faith. That first, and that last. Yet it is also true to say something similar about Bultmann and Brunner so far as the central dogmatic core is concerned. Though for Bultmann the priority is given to the Bible text, and its critical apppropriation in terms that make sense and connect with contemporary thought. It is a fascinating disagreement between Barth and Bultmann. Both honour the biblical text, and both affirm the centrality of Christ for Christian theology. It is at the point of delivery, the preaching of the Word, that they so deeply disagree about what a sermon should be, and do.