Salman Rushdie, Thomas Friedman, Nicholas Kristof and Mansour al-Nogaidan are among the well-intentioned people who have called for an Islamic Reformation. They should be careful what they wish for.

The Protestant Reformation did precede the things these men admire about modernity in the West, including women's emancipation, political liberty, scientific breakthroughs, the wealth and opportunity created by the Industrial Revolution, and permission to think freely regarding God. But all this came later, and the Reformation was only part of what brought them about.

The Reformation was a time of intense focus on God and what He requires of people. As a movement, it was enthusiastic, narrow and far from tolerant. It and the Counter-Reformation brought two centuries of repression, war and massacre to the West. It's unlikely that anyone who lived through it would consider wishing a Reformation on Muslims.

And yet, even as some hope for such a turn of events — presuming, it seems, a certain conclusion — a Reformation is sweeping through the Muslim world. Westerners are generally aware that the Shiite and Sunni sects of Islam are struggling for dominance in Iraq. But more broadly, the words and doctrine promoted by the Muslim Brotherhood and the Salafis or Wahhabists are eerily similar to those of our 16th-century forebears.

Like the followers of Martin Luther and John Calvin, Islamic reformers reject the interpretations of generations of scholars in favor of seeking the word of God directly in scripture. Normative Islam follows one or another school of interpretation of scripture, known as a Madhab. Careful study leads students to understand that God's word is often nuanced. Nuance is not the stuff of reform. Salafi reformers argue that Muslims should ignore generations of sages, read the Koran and Hadith for themselves, and act on the truth they find. A popular Salafi quote from the early Islamic jurist Abu Hanifa reads: When a passage (Hadith) is found to be authentic (saheeh) then that is my path (Madhab).

As Luther put it: Sola scriptura (Scripture alone).

Protestant determination to follow the word of God straight from the Bible was accompanied by a desire to purify Christianity by emulating the beliefs and practices of the early church. Hassan al Banna, founder of the Muslim Brotherhood; Sayyid Qutb, a leading Muslim Brotherhood thinker; and Ibn Wahab, the founder of modern Salafi, or Wahhabist, Islam, call upon Muslims to return to the uncorrupted beliefs and practices of early Islam and to become as pure as Salafis, or the first three generations of Muslims. To become, as it were, Puritans.

The call to purity appeals in part because in the Muslim world today corrupt holders of wealth and power resist moderate attempts at reform, much as the corrupt holders of wealth and power in the church and states in Luther's Europe resisted moderate reform.

Western pundits have debated whether Arabs who voted for Hamas or the Muslim Brotherhood in the Palestinian and Egyptian parliamentary elections were voting for the Islamist religious program or voting against corruption. Surely it was a two-for-one deal. To vote for the Muslim Brotherhood or Hamas is to vote against corruption and for returning to the purity of the days of the prophet Muhammad. This was a compelling idea when preached by Calvin. It still is.

There are, of course, differences between the Protestant and Islamic reformations. In Islam today it is usually radical reformers who have reached first for the sword. In the European Reformation, things became tense when a determined minority demanded reform, but in general it was those church and state officials who held power who first resorted to violence. In some European countries, the Reformation or the Counter-Reformation produced a rigid orthodoxy that stifled development for generations. In other countries, the wars of religion were followed by the Enlightenment.

Muslims might not follow a European course. They will choose whether they prefer societies shaped by Sayyid Qutb, who advocated closing the Islamic mind to everything but the ancient texts, or Ibn Rushd (also known as Averroes), who preferred the open embrace of all knowledge.

In the near term, though, the Islamic Reformation will divide Muslim society as the Reformation divided Europe. A fervent minority in many countries is already pressing for narrow interpretations on issues such as veiling, whether to listen to music and replacing secular laws with religious codes. As we have seen in Europe and more recently in Afghanistan, we are likely to see Muslim Puritans take over communities where they are far from being the majority. Meanwhile, the majority has yet to construct an effective ideological defense of moderation.

Diana Muir is writing a book about the history of nations and nationalism. She is the author of "Bullough's Pond; Economy and Ecosystem in New England." She wrote this commentary for The Washington Post.