In 1967, a law student at the University of Khartoum named Abdullahi Ahmed an-Naim was looking for a way to spend a summer evening in his home town, a railway junction on the banks of the Nile in northern Sudan. No good movies were showing at the local cinemas, so he went with a friend to hear a public lecture by Mahmoud Muhammad Taha, an unorthodox Sudanese mystic with a small but ardent following. Taha’s subject, “An Islamic Constitution: Yes and No,” tantalized Naim. In the years after Sudan became independent, in 1956, the role of Islam in the state was fiercely debated by traditional Sufists, secular Marxists, and the increasingly powerful Islamists of the Muslim Brotherhood, who, at the time, were led in Sudan by Hasan al-Turabi, a legal scholar. Politically, Naim was drifting toward the left, but his upbringing in a conservative Muslim home had formed him. “I was very torn,” Naim recently recalled. “I am a Muslim, but I couldn’t accept Sharia”—Islamic law. “I studied Sharia and I knew what it said. I couldn’t see how Sudan could be viable without women being full citizens and without non-Muslims being full citizens. I’m a Muslim, but I couldn’t live with this view of Islam.”

Naim’s quandary over Islam was an intensely personal conflict—he called it a “deadlock.” What he heard at Taha’s lecture resolved it. Taha said that the Sudanese constitution needed to be reformed, in order to reconcile “the individual’s need for absolute freedom with the community’s need for total social justice.” This political ideal, he argued, could be best achieved not through Marxism or liberalism but through Islam—that is, Islam in its original, uncorrupted form, in which women and people of other faiths were accorded equal status. As Naim listened, a profound sense of peace washed over him; he joined Taha’s movement, which came to be known as the Republican Brothers, and the night that had begun so idly changed his life.

It is a revelation story, and some version of it is surprisingly easy to hear in the Islamic world, especially among educated middle-class Muslims in the generation that came after the failures of nationalism and Socialism. During a recent trip to Sudan, I visited the University of Khartoum, which is housed in a collection of mostly colonial-era, earth-colored brick buildings in the city center, where I met a woman named Suhair Osman, who was doing graduate work in statistics. In 1993, at the age of eighteen, she spent the year between high school and college in her parents’ house on the Blue Nile, south of Khartoum, asking herself theological questions. As a schoolgirl, she had been taught that sinners would be eternally tormented after death; she couldn’t help feeling sorry for them, but she didn’t dare speak about it in class. Would all of creation simply end either in fire or in Paradise? Was her worth as a woman really no more than a quarter that of a man, as she felt Islamic law implied by granting men the right to take four wives? Did believers really have a duty to kill infidels? One day, Osman took a book by Taha off her father’s shelf, “The Koran, Mustapha Mahmoud, and Modern Understanding,” published in 1970. By the time she finished it, she was weeping. For the first time, she felt that religion had accorded her fully equal status. “Inside this thinking, I’m a human being,” she said. “Outside this thinking, I’m not.” It was as if she had been asleep all her life and had suddenly woken up: the air, the taste of water, food, even the smell of things changed. She felt as if she were walking a little off the ground.

The quest for spiritual meaning is typically a personal matter in the West. In the Islamic world, it often leads the seeker into some kind of collective action, informed by utopian aspiration, that admits no distinction between proselytizing, social reform, and politics. The Islamic revival of the past several decades is the history of millions of revelation stories. Far from being idiosyncratic or marginal, they have combined into a tremendous surge that is now a full-time concern of the West. Renewal and reform—in Arabic, tajdid and islah—have an ambiguous and contested meaning in the Islamic world. They signify a stripping away of accumulated misreadings and wrong or lapsed practices, as in the Protestant Reformation, and a return to the founding texts of the Koran and the Sunna—guidelines based on the recorded words and deeds of the Prophet. But, beyond that, what is the nature of the reform? The father of one modern revelation story is Sayyid Qutb, the Egyptian religious thinker who, after advocating jihad and the overthrow of secular Arab regimes, was hanged by Gamal Abdel Nasser in 1966. Qutb’s prison writings reject modernity, with its unholy secularism, and call on adherents of Islam to return to a radically purified version of the religion, which was established in the seventh century. Among the idealistic young believers who found in his books a guide to worldwide Islamization were Ayman al-Zawahiri and Osama bin Laden. With the newest generation of jihadis—Qutb’s spiritual grandchildren—the ideas of the master have been construed as a justification for killing just about anyone in the name of reviving the days of the Prophet; earlier this year, several Baghdad falafel venders were killed by Islamists because falafel did not exist in the seventh century.

Mahmoud Muhammad Taha is the anti-Qutb. Taha, like Qutb, was hanged by an Arab dictatorship; he was executed, in 1985, for sedition and apostasy, after protesting the imposition of Sharia in Sudan by President Jaafar al-Nimeiri. In death, Taha became something rare in contemporary Islam: a moderate martyr. His method of reconciling Muslim belief with twentieth-century values was, in its way, every bit as revolutionary as the contrary vision of Qutb. It is one sign of the current state of the struggle over Islam that, in the five years since September 11th, millions of people around the world have learned the name Sayyid Qutb while Mahmoud Muhammad Taha’s is virtually unknown. Islamism has taken on the frightening and faceless aspect of the masked jihadi, the full-length veil, the religious militia, the blurred figure in a security video, the messianic head of state, the anti-American mob. At Islam’s core, in the countries of the Middle East from Egypt to Iran, tajdid and islah have helped push societies toward extremes of fervor, repression, and violence. But on the periphery, from Senegal to Indonesia—where the vast majority of Muslims live—Islamic reform comes in more varieties than most Westerners imagine. At the edges, the influence of American policy and the Israeli-Palestinian siege is less overwhelming, and it is easier to see that the real drama in Islam is the essential dilemma addressed by Taha: how to revive ancient sacred texts in a way that allows one to live in the modern world.

Taha was born sometime early in the twentieth century—scholars say 1909 or 1911—in a town on the eastern bank of the Blue Nile, two hours south of Khartoum, called Rufaa. It is a somnolent, heat-drenched town, one of those silent places—they stretch from one harsh end to the other of the North African region known as the Sahel—where mystical movements often begin. In the years before Sudan’s independence, Taha was educated as a civil engineer in a British-run university, and after working briefly for Sudan Railways he started his own engineering business. He absorbed modern political and social ideas by reading widely, if incompletely, in the works of Marx, Lenin, Russell, Shaw, and Wells. In 1945, he founded an anti-monarchical political group, the Republican Party, and was twice imprisoned by the British authorities: first for writing pro-independence pamphlets, and then for leading an uprising in Rufaa against the arrest of a local woman who had subjected her daughter to a particularly severe form of female circumcision. (Taha opposed the practice but believed that the colonial edict banning it would only make it more widespread.) His second imprisonment lasted two years, and when he was released, in 1948, he entered a period of seclusion, prayer, and fasting in a small mud building in the courtyard next to his in-laws’ house. By the time I visited Rufaa, in July, the hut had been torn down and replaced, and the house was occupied by a family of southern Sudanese.