In a recent post, I tried to describe one reason why theology can be hard to understand: because any specialized human endeavor requires a linguistic shorthand. But there are other reasons as well. One of them is that reality itself, in both its physical and metaphysical dimensions, is complicated. The mathematics behind ordinary Newtonian physics is complex enough, to say nothing of quantum mechanics, superstrings, and non-Euclidean geometry. A typical computer model to describe the folding of a single protein – something that takes place trillions of times each second within our bodies – may require a network of thousands of computers to run. Whatever the relationship of the Ultimate Reality to the diminishingly small portion of reality that we are aware of, it would be astonishing if it were not complex, nuanced and all-but incomprehensible. (Indeed, probably the best way that we could expect to wrap our primate brains around any of it would be through symbols and stories: or as Tolkien and Lewis would put it, through myths that actually happened.)
And however complicated reality might be to describe, the initial process of producing those descriptions is more convoluted yet. In any branch of science, hard or soft, theories are produced, elaborated and abandoned in a mind-numbing profusion. Once the scientists in any particular sub-specialty have settled on a particular theory, it's not difficult for the remaining hundreds or thousands of scientists in their particular branch of knowledge to understand it: but, until that happens, most likely only a few dozen are following the conversation closely enough to be able to judge the state of the debate at any given point, or to critique the work of their follow sub-specialists. Today, you can explain Einstein's theories of relativity to any reasonably intelligent high-school student; but when he first proposed them, only a very few physicists could understand the mathematics he was using. The journal articles that bedeviled my early theological reading, and my foray through Barth, were difficult precisely because they weren't predigested: they were the equivalent of reading Einstein's "The Electrodynamics of Moving Bodies", not a beginning physics textbook.
To put it another way, one of the main reasons that theologians seem narrow is because humans are narrow. None of us can get a handle on all of reality. We all have to take the little chunks and slices that we're interested in, work with those in whatever ways we can, and pretty much ignore everything else. Call it tribal or parochial if you like, but it's human. It's how scientists work, how computer programmers work, and for that matter, how plumbers and carpet-cleaners and mountain climbers work.
Of course, probably nothing we spend our waking hours on is really as important as we think, including theology. But it's difficult to imagine any alternative: we can't stop being human. Just because you can't understand a theological discussion without acquainting yourself with the background behind it doesn't mean it isn't worth having, or that the scholars engaged in that discussion have locked themselves into ivory towers.
Of course, just because some theology can be difficult and still be valuable, doesn't mean that a given theological work is valuable because it's difficult – though I've known plenty of folks who seemed to think so.