A page from an eleventh- or twelfth-century Persian Koran. Courtesy of the Arthur M. Sackler Museum, Harvard University Art Museums, Fund for the Acquisition of Islamic Art.

OUGHLY equivalent in length to the New Testament, the Koran is divided into 114 sections, known as suras, that vary dramatically in length and form. The book's organizing principle is neither chronological nor thematic -- for the most part the suras are arranged from beginning to end in descending order of length. Despite the unusual structure, however, what generally surprises newcomers to the Koran is the degree to which it draws on the same beliefs and stories that appear in the Bible. God (Allah in Arabic) rules supreme: he is the all-powerful, all-knowing, and all-merciful Being who has created the world and its creatures; he sends messages and laws through prophets to help guide human existence; and, at a time in the future known only to him, he will bring about the end of the world and the Day of Judgment. Adam, the first man, is expelled from Paradise for eating from the forbidden tree. Noah builds an ark to save a select few from a flood brought on by the wrath of God. Abraham prepares himself to sacrifice his son at God's bidding. Moses leads the Israelites out of Egypt and receives a revelation on Mount Sinai. Jesus -- born of the Virgin Mary and referred to as the Messiah -- works miracles, has disciples, and rises to heaven.

The Koran takes great care to stress this common monotheistic heritage, but it works equally hard to distinguish Islam from Judaism and Christianity. For example, it mentions prophets -- Hud, Salih, Shu'ayb, Luqman, and others -- whose origins seem exclusively Arabian, and it reminds readers that it is "A Koran in Arabic, / For people who understand." Despite its repeated assertions to the contrary, however, the Koran is often extremely difficult for contemporary readers -- even highly educated speakers of Arabic -- to understand. It sometimes makes dramatic shifts in style, voice, and subject matter from verse to verse, and it assumes a familiarity with language, stories, and events that seem to have been lost even to the earliest of Muslim exegetes (typical of a text that initially evolved in an oral tradition). Its apparent inconsistencies are easy to find: God may be referred to in the first and third person in the same sentence; divergent versions of the same story are repeated at different points in the text; divine rulings occasionally contradict one another. In this last case the Koran anticipates criticism and defends itself by asserting the right to abrogate its own message ("God doth blot out / Or confirm what He pleaseth").

Criticism did come. As Muslims increasingly came into contact with Christians during the eighth century, the wars of conquest were accompanied by theological polemics, in which Christians and others latched on to the confusing literary state of the Koran as proof of its human origins. Muslim scholars themselves were fastidiously cataloguing the problematic aspects of the Koran -- unfamiliar vocabulary, seeming omissions of text, grammatical incongruities, deviant readings, and so on. A major theological debate in fact arose within Islam in the late eighth century, pitting those who believed in the Koran as the "uncreated" and eternal Word of God against those who believed in it as created in time, like anything that isn't God himself. Under the Caliph al-Ma'mun (813-833) this latter view briefly became orthodox doctrine. It was supported by several schools of thought, including an influential one known as Mu'tazilism, that developed a complex theology based partly on a metaphorical rather than simply literal understanding of the Koran.

By the end of the tenth century the influence of the Mu'tazili school had waned, for complicated political reasons, and the official doctrine had become that of i'jaz, or the "inimitability" of the Koran. (As a result, the Koran has traditionally not been translated by Muslims for non-Arabic-speaking Muslims. Instead it is read and recited in the original by Muslims worldwide, the majority of whom do not speak Arabic. The translations that do exist are considered to be nothing more than scriptural aids and paraphrases.) The adoption of the doctrine of inimitability was a major turning point in Islamic history, and from the tenth century to this day the mainstream Muslim understanding of the Koran as the literal and uncreated Word of God has remained constant.

ERD-R. Puin speaks with disdain about the traditional willingness, on the part of Muslim and Western scholars, to accept the conventional understanding of the Koran. "The Koran claims for itself that it is 'mubeen,' or 'clear,'" he says. "But if you look at it, you will notice that every fifth sentence or so simply doesn't make sense. Many Muslims -- and Orientalists -- will tell you otherwise, of course, but the fact is that a fifth of the Koranic text is just incomprehensible. This is what has caused the traditional anxiety regarding translation. If the Koran is not comprehensible -- if it can't even be understood in Arabic -- then it's not translatable. People fear that. And since the Koran claims repeatedly to be clear but obviously is not -- as even speakers of Arabic will tell you -- there is a contradiction. Something else must be going on."

Trying to figure out that "something else" really began only in this century. "Until quite recently," Patricia Crone, the historian of early Islam, says, "everyone took it for granted that everything the Muslims claim to remember about the origin and meaning of the Koran is correct. If you drop that assumption, you have to start afresh." This is no mean feat, of course; the Koran has come down to us tightly swathed in a historical tradition that is extremely resistant to criticism and analysis. As Crone put it in Slaves on Horses,

The Biblical redactors offer us sections of the Israelite tradition at different stages of crystallization, and their testimonies can accordingly be profitably compared and weighed against each other. But the Muslim tradition was the outcome, not of a slow crystallization, but of an explosion; the first compilers were not redactors, but collectors of debris whose works are strikingly devoid of overall unity; and no particular illuminations ensue from their comparison.

If our goal is to comprehend the way in which Muslims of the late 2nd/8th and 3rd/9th centuries [Islamic calendar / Christian calendar] understood the origins of their society, then we are very well off indeed. But if our aim is to find out "what really happened," in terms of reliably documented answers to modern questions about the earliest decades of Islamic society, then we are in trouble.

attribution of several, partially overlapping, collections of logia (exhibiting a distinctly Mosaic imprint) to the image of a Biblical prophet (modified by the material of the Muhammadan evangelium into an Arabian man of God) with a traditional message of salvation (modified by the influence of Rabbinic Judaism into the unmediated and finally immutable word of God).

NDEED, for more than a century there have been public figures in the Islamic world who have attempted the revisionist study of the Koran and Islamic history -- the exiled Egyptian professor Nasr Abu Zaid is not unique. Perhaps Abu Zaid's most famous predecessor was the prominent Egyptian government minister, university professor, and writer Taha Hussein. A determined modernist, Hussein in the early 1920s devoted himself to the study of pre-Islamic Arabian poetry and ended up concluding that much of that body of work had been fabricated well after the establishment of Islam in order to lend outside support to Koranic mythology. A more recent example is the Iranian journalist and diplomat Ali Dashti, who in his Twenty Three Years: A Study of the Prophetic Career of Mohammed (1985) repeatedly took his fellow Muslims to task for not questioning the traditional accounts of Muhammad's life, much of which he called "myth-making and miracle-mongering."

Abu Zaid also cites the enormously influential Muhammad 'Abduh as a precursor. The nineteenth-century father of Egyptian modernism, 'Abduh saw the potential for a new Islamic theology in the theories of the ninth-century Mu'tazilis. The ideas of the Mu'tazilis gained popularity in some Muslim circles early in this century (leading the important Egyptian writer and intellectual Ahmad Amin to remark in 1936 that "the demise of Mu'tazilism was the greatest misfortune to have afflicted Muslims; they have committed a crime against themselves"). The late Pakistani scholar Fazlur Rahman carried the Mu'tazilite torch well into the present era; he spent the later years of his life, from the 1960s until his death in 1988, living and teaching in the United States, where he trained many students of Islam -- both Muslims and non-Muslims -- in the Mu'tazilite tradition.

Such work has not come without cost, however: Taha Hussein, like Nasr Abu Zaid, was declared an apostate in Egypt; Ali Dashti died mysteriously just after the 1979 Iranian revolution; and Fazlur Rahman was forced to leave Pakistan in the 1960s. Muslims interested in challenging orthodox doctrine must tread carefully. "I would like to get the Koran out of this prison," Abu Zaid has said of the prevailing Islamic hostility to reinterpreting the Koran for the modern age, "so that once more it becomes productive for the essence of our culture and the arts, which are being strangled in our society." Despite his many enemies in Egypt, Abu Zaid may well be making progress toward this goal: there are indications that his work is being widely, if quietly, read with interest in the Arab world. Abu Zaid says, for example, that his The Concept of the Text (1990) -- the book largely responsible for his exile from Egypt -- has gone through at least eight underground printings in Cairo and Beirut.

Another scholar with a wide readership who is committed to re-examining the Koran is Mohammed Arkoun, the Algerian professor at the University of Paris. Arkoun argued in Lectures du Coran (1982), for example, that "it is time [for Islam] to assume, along with all of the great cultural traditions, the modern risks of scientific knowledge," and suggested that "the problem of the divine authenticity of the Koran can serve to reactivate Islamic thought and engage it in the major debates of our age." Arkoun regrets the fact that most Muslims are unaware that a different conception of the Koran exists within their own historical tradition. What a re-examination of Islamic history offers Muslims, Arkoun and others argue, is an opportunity to challenge the Muslim orthodoxy from within, rather than having to rely on "hostile" outside sources. Arkoun, Abu Zaid, and others hope that this challenge might ultimately lead to nothing less than an Islamic renaissance.

THE gulf between such academic theories and the daily practice of Islam around the world is huge, of course -- the majority of Muslims today are unlikely to question the orthodox understanding of the Koran and Islamic history. Yet Islam became one of the world's great religions in part because of its openness to social change and new ideas. (Centuries ago, when Europe was mired in its feudal Dark Ages, the sages of a flourishing Islamic civilization opened an era of great scientific and philosophical discovery. The ideas of the ancient Greeks and Romans might never have been introduced to Europe were it not for the Islamic historians and philosophers who rediscovered and revived them.) Islam's own history shows that the prevailing conception of the Koran is not the only one ever to have existed, and the recent history of biblical scholarship shows that not all critical-historical studies of a holy scripture are antagonistic. They can instead be carried out with the aim of spiritual and cultural regeneration. They can, as Mohammed Arkoun puts it, demystify the text while reaffirming "the relevance of its larger intuitions."

Increasingly diverse interpretations of the Koran and Islamic history will inevitably be proposed in the coming decades, as traditional cultural distinctions between East, West, North, and South continue to dissolve, as the population of the Muslim world continues to grow, as early historical sources continue to be scrutinized, and as feminism meets the Koran. With the diversity of interpretations will surely come increased fractiousness, perhaps intensified by the fact that Islam now exists in such a great variety of social and intellectual settings -- Bosnia, Iran, Malaysia, Nigeria, Saudi Arabia, South Africa, the United States, and so on. More than ever before, anybody wishing to understand global affairs will need to understand Islamic civilization, in all its permutations. Surely the best way to start is with the study of the Koran -- which promises in the years ahead to be at least as contentious, fascinating, and important as the study of the Bible has been in this century.