From the introduction to Tools of Dominion: The Case Laws of Exodus.
This is a fat book. I have no illusions about its becoming a best-seller. But I hold to what I call the fat book theory of social transformation. Most of the major turning points in Western history have had fat books at their center. The Bible is certainly a fat book. Augustine's City of God is a fat book, and by adhering to the biblical worldview, it restructured Western civilization's concept of history. Thomas Aquinas' Summa Theologica is a fat book, and it gave the medieval West the crucial synthesis of scholastic philosophy, an in- tellectual tradition still defended by a handful of Roman Catholic conservatives and (implicitly, at least) by most contemporary Protestant fundamentalist philosophers. John Calvin's Institutes of the Christian Religion is a fat book, and it structured a large segment of Reformation theology.
Christians have not been the only social transformationists who have written fat books that have changed Western civilization. Thomas Hobbes' Leviathan is a fat book, and it launched the long tradition of social contract political theory. Immanuel Kant's Critique of Pure Reason is a fat book, and you just about have to take his Critique of Practical Reason as its companion volume. This set restructured modern philosophy, and in the twentieth century, theology (by way of Karl Barth and Emil Brunner). William Blackstone's Commentaries on the Laws of England is a four-volume fat book, yet it was read by just about every lawyer in the British colonies after 1765. The Federalist is fat. (Of course, it had its greatest initial effect as a series of newspaper articles, 1787-88, during the debate over the ratification of the U.S. Constitution, which gives us some comparative indica- tion of the recent effects of humanist public school programs to achieve universal literacy in the United States. Try to get the average American newspaper reader to read, digest, and comment on The Federalist.)
A decade after Blackstone's Commentaries, came Adam Smith's Wealth of Nations, a fat book. Karl Marx's Das Kapital is a fat book; if you include the two posthumous volumes, it is a very fat book. If you include his posthumous multi-volume Theories of Surplus Value, it is positively obese. All these fat books have sat on library shelves and have intimidated people, generation after generation. And a handful of influential people actually went to the effort to read them, subsequently believed them, and then wrote more books in terms of them.