Why do theologians write so much? I’m going to take the case of Rudolf Bultmann because the problem is particularly acute with him, but it applies to most, including Karl Barth. Barth’s Church Dogmatics alone is over six million words. Together they are the most influential Protestant theologians of the 20th century.
They write so much because they are writing about what cannot be spoken, or written. The kerygma (κήρυγμα), which means message or proclamation, refers in general to the gospels, and in Bultmann’s work to the decision to follow the message of Advent, that Christ is risen and we must choose to believe and act accordingly.
Trouble is, the kerygma is prelinguistic.
As counterintuitive as it may initially appear, the logical conclusion is that the kerygma is essentially prelinguistic. (Congdon, p 74)
This doesn’t make words irrelevant, but it sets their limit. If “the purpose of theology is to bring to speech the actual event in which one encounters the living God,” then Bultmann’s project is impossible.