From Eamon Duffy's essay in the New York Review of Books, March 29:
Early Christianity was more than a new religion: it brought with it a revolutionary shift in the information technology of the ancient world. That shift was to have implications for the cultural history of the world over the next two millennia at least as momentous as the invention of the Internet seems likely to have for the future. Like Judaism before it and Islam after it, Christianity is often described as "a religion of the Book." The phrase asserts both an abstraction—the centrality of authoritative sacred texts and their interpretation within the three Abrahamic religions—and also a simple concrete fact—the importance of a material object, the book, in the history and practice of all three traditions….
Our modern book form, the codex, in fact evolved from the ancient equivalent of the stenographer's pad, bundles of wooden tablets linked with string hinges and coated with wax, on which information could be jotted with a stylus (often in shorthand). When the information was no longer needed, the wax could be heated and smoothed, and the tablets reused. The first papyrus and (especially) parchment books of pages were recyclable in just the same way, folded and stitched bundles written on with soluble ink that could be washed off to leave the pages blank again. To inscribe the words of Holy Scripture on such jotting pads would demean its sacred character and authority….
Why should the new religion have adopted this down-market and unfashionable book technology? The codex, it is true, has obvious practical advantages. Being written on both sides of the page, it is more economical than the roll, it can be readily indexed, it can be leafed through quickly to find a particular place, and it is more robustly portable. But these practical advantages, which certainly contributed to its eventual adoption as the normative form of the book, do not adequately explain the early Christians' exclusive preference for the form, even for their copies of the Jewish scriptures, which must of course have been transcribed from rolls. Historians have speculated that difference from Judaism may have been the point—that the codex was adopted to distance the emergent Church from its origins within the religion of Israel, or perhaps in an attempt to signal that its foundational texts were indeed a sort of sacred stenography, the living transcript of apostolic experience, taken from the mouths of the first witnesses.