Book excerpt: This monumental study of medieval law and sexual conduct explores the origin and develpment of the Christian church's sex law and the systems of belief upon which that law rested. Focusing on the Church's own legal system of canon law, James A. Brundage offers a comprehensive history of legal doctrines–covering the millennium from A.D. 500 to 1500–concerning a wide variety of sexual behavior, including marital sex, adultery, homosexuality, concubinage, prostitution, masturbation, and incest. His survey makes strikingly clear how the system of sexual control in a world we have half-forgotten has shaped the world in which we live today. The regulation of marriage and divorce as we know it today, together with the outlawing of bigamy and polygamy and the imposition of criminal sanctions on such activities as sodomy, fellatio, cunnilingus, and bestiality, are all based in large measure upon ideas and beliefs about sexual morality that became law in Christian Europe in the Middle Ages. "Brundage's book is consistently learned, enormously useful, and frequently entertaining. It is the best we have on the relationships between theological norms, legal principles, and sexual practice."—Peter Iver Kaufman, Church History