The Charlie Hebdo massacre once again has politicians and the media dancing around the question of whether there might be something a little bit special about this one particular religion, Islam, that causes its adherents to go around killing people.

It is not considered acceptable in polite company to entertain this possibility. Instead, it is necessary to insist, as a New York Times article does, that “Islam is no more inherently violent than other religions.” This, mind you, was in an article on how Muslims in the Middle East are agonizing over the violent legacy of their religion.

It is obviously true that all major religions have had violent periods, or periods in which the religion has coexisted with violence. Even those mellow pacifist Buddhists. These days, especially the Buddhists, who are currently fomenting a pogrom against a Muslim minority in Burma.

But in today’s context, it’s absurd to equate Islam and Christianity. Pointing to the Spanish Inquisition tends to undermine the point rather than confirm it: if you have to look back three hundred years to find atrocities, it’s because there are so few of them today. The mass crimes committed under the name of Islam, by contrast, are fresh and openly boasted about.

As an atheist, I have no god in this fight, so to speak. I don’t think the differences between religions make one more valid than another. But as the Charlie Hedbo attack reminds us, there is a big practical difference between them. In fact, the best argument against the equivalence of Christianity and Islam is that no one acts even remotely as if this were true. We feel free to criticize and offend Christians without a second thought—thanks, guys, for being so cool about that—but antagonizing Muslims takes courage. More courage than a lot of secular types in the West can usually muster.

So it’s a matter of some practical urgency to figure out: what is the difference? What are its root causes?

As I see it, the main danger posed by any religion to its dissenters and unbelievers lies in the rejection of reason, which cuts off the possibility of discussion and debate, leaving coercion as an acceptable substitute. I’m with Voltaire on that one: “If we believe absurdities, we will commit atrocities.” But all religions are different and have different doctrines which are shaped over their history—and as we shall see, that includes different views on precisely such core issues as the role of reason and persuasion.

I should preface this by saying that I am no expert on theology, particularly Muslim theology. Yet there are a number of big, widely documented differences between Christianity and Islam that can be seen in the traditions established by their history and in the actual content of their religious doctrines.

The life of Christ versus the life of Mohammed.

Mohammed was a conqueror who gained worldly political power in his lifetime and used it to persecute opponents and impose his religion. He also fully enjoyed the worldly perks of being a tyrant, including multiple wives. Jesus, by contrast, was basically a pacifist whose whole purpose on earth was to allow himself to be tortured to death.

He even explicitly forbade his followers to use force to defend him. Here’s John, Chapter 18: “Then Simon Peter having a sword drew it, and smote the high priest’s servant, and cut off his right ear…. Then said Jesus unto Peter, Put up thy sword into the sheath: the cup which my Father hath given me, shall I not drink it?”

This does not imply that all Christians ought to be pacifists. But it certainly sets a tone for the religion. The life of the founder of a religion is held up to his followers as a model for how they should live their own lives. The life of Mohammed tells the Muslim that he should expect to rule, whereas the life of Christ tells the Christian he should expect to sacrifice and serve. Which leads us to a deeper doctrinal difference.

“What you do to the least of these, you do to me.”

In Matthew, Chapter 25, Christ tells his followers what will happen during the final judgment, when he separates the righteous from the wicked.

Then shall the King say unto them on his right hand, Come, ye blessed of my Father, inherit the kingdom prepared for you from the foundation of the world: For I was an hungred, and ye gave me meat: I was thirsty, and ye gave me drink: I was a stranger, and ye took me in: Naked, and ye clothed me: I was sick, and ye visited me: I was in prison, and ye came unto me.



Then shall the righteous answer him, saying, Lord, when saw we thee an hungred, and fed thee? or thirsty, and gave thee drink? When saw we thee a stranger, and took thee in? or naked, and clothed thee? Or when saw we thee sick, or in prison, and came unto thee?



And the King shall answer and say unto them, Verily I say unto you, Inasmuch as ye have done it unto one of the least of these my brethren, ye have done it unto me.

Similarly, there is an episode during the Last Supper when the apostles are squabbling about which of them is greatest. Christ intervenes and tells them that the greatest is he who serves others the most.

And he said unto them, The kings of the Gentiles exercise lordship over them; and they that exercise authority upon them are called benefactors. But ye shall not be so: but he that is greatest among you, let him be as the younger; and he that is chief, as he that doth serve.

This is a very profound idea that goes against the grain of most of human history. I’m a big fan of the Classical world, but the pagans still regarded it as normal, right, and natural that the physically strong set the terms for everyone else. Thucydides famously summed it up in the Melian Dialogue: “The strong do as they can and the weak suffer what they must.” Thucydides was clearly critical of that view, but the Classical world didn’t have a clear alternative. As far as I know, Christ was the first to insist that even the lowest, least significant person has value and that we will be judged by how we treat him.

The distinctive idea here is not a belief in self-sacrifice—Islam, with its emphasis on the glory of dying in battle, has that idea in abundance. Nor is it the idea of a duty to serve others—Communist regimes were built on the idea that the individual exists only to serve the collective. Instead, it is the idea that each individual has a supreme and sacred value. Even Ayn Rand declared this to be the idea from Christianity that most impressed her.

Islam has no corresponding idea. The news is constantly bringing us a story of some imam somewhere declaring it consistent with Islam for a man to beat his wife, and the rise of the Islamic State in Syria has provided us current examples of Islam sanctioning slavery, including the capture and systematic rape of sex slaves. This is a religion that is still very much in the “rights of the conqueror” mode, in which the strong do what they can and the weak suffer what they must.

Again, this goes back to the beginning. Consider the story, from one of the earliest Arab biographies of Mohammed, of Asma bint Marwan, an Arab poet in Medinah who spoke out against the rise of Mohammed. According to legend, he asked his followers, “Who will rid me of the daughter of Marwan?” (His version of Henry II’s “Will no one rid me of this meddlesome priest?”) One of them took it on himself to sneak into her house and murder her in her sleep. There are questions about the authenticity of the story, but the fact that it was widely believed and reported indicates the example Mohammed set.

To be sure, this brutal attitude is partly because of the backwardness of some of the quasi-feudal societies that are majority-Muslim, where divisions of tribe and caste still dominate. But then again, Islam hasn’t done much to elevate those societies, despite having more than a thousand years to do so.

The early history of Christianity vs. Islam

Christians started as a persecuted minority in a pagan society, so that gives them a certain comfort with being powerless. Those who find themselves out of step with the sinful modern world regard this as more or less the normal state of things.

The early history of Islam, by contrast, was further conquest and dominance, as Muslim invaders marched out into Persia and across North Africa. That’s why Muslims tend to look at the modern situation, in which other creeds and political systems are wealthier and wield greater military power, as an aberration that is not to be tolerated.

This history is connected to a specific doctrinal issue.

The kingdom of god vs. the kingdom of man.

When you’re a persecuted minority, it’s more natural to say that the ultimate reward and total justice have to be found in another world, because you know you’re not going to get them in the decadent Roman Empire. In Christianity, this produced a distinction between the kingdom of God and the kingdom of man. When Pilate asks him if he is a king, Jesus responds, “My kingdom is not of this world: if my kingdom were of this world, then would my servants fight, that I should not be delivered to the Jews: but now is my kingdom not from hence.”

This idea is extensively developed in Christian theology and is widely accepted among religious conservatives today as the main explanation for the failure of Communism and other utopian schemes: they were arrogant, misguided attempts to achieve heaven on earth. Or if you are inclined to the use of unnecessarily long and obscure words, this is referred to as trying to “immanentize the eschaton.”

The idea is that human beings are not capable of achieving the ultimate holy order of things in this world, so it is folly to try.

But when your prophet is the dictator, it’s more tempting to think that you can just mandate a perfect society. Hence the Islamist obsession with creating a pure Islamic State, usually with a special division of zealots who call themselves something like the Ministry for the Promotion of Virtue and the Prevention of Vice, whose job is to enforce a long list of intrusive religious prohibitions. An Islamic state is the kingdom of God brought to earth—exactly the approach that has been widely rejected at various points in Christian theology.

The different roles of “falsafa.”

There is another important legacy of Christianity’s early history among the pagans—in this case, not a reaction against pagan rule, but a part of the Classical influence that rubbed off on Christianity.

Christianity took hold among Greeks and Romans steeped in the Classical philosophical tradition, and that left its mark. The now-retired pope, Benedict XVI—who I’m really missing right now, by the way—made this the central point of an important speech he gave in 2006 at the University of Regensburg, in which he addressed the relationship between Christianity and Islam. Benedict argued that “the critically purified Greek heritage forms an integral part of Christian faith,” and defended the “Hellenization” of Christianity. (More on this later.) There was some controversy about this within early Christianity—Tertullian famously asked, “What has Athens to do with Jerusalem?”—and at first the anti-Classical side won out. But those early controversies made it easier for Christianity to re-absorb Classical ideas during the late Middle Ages and Renaissance.

Islam went through an opposite progression. It encountered Classical science and philosophy, “falsafa” in Arabic, during its conquest of various Mediterranean countries, and the Muslim world would produce great scientists and philosophers steeped in the ideas of the Greeks, including ibn Sina (Avicenna) in Persia and ibn Rushd (Averroes) in Muslim Spain. But by the late Middle Ages, just as the West was rediscovering Classical philosophy, the Muslim world purged it. This is generally blamed on the theologian al-Ghazali, who denounced “The Incoherence of the Philosophers” and caused Muslim theologians to reject the Classical influence as incompatible with faith. The result is that Islam allows much less room for philosophical discussion and debate over the meaning of the religion.

Again, this history is connected to a deeper doctrinal issue.

Is God rational?

This was the issue Benedict focused on in his Regensburg speech. He approvingly cited a dialogue in which one of the Byzantine emperors was debating with a Muslim and argued that in Christian theology, God is rational: he acts according to reason and is understandable by reason. He cited a Biblical passage about God being “Logos”—which means both “word” and “reason” in Greek—as evidence that “the world comes from reason” as part of the animating spirit of God’s creation.

Islam rejects this view. Al-Ghazali even rejected the law of cause and effect. The Muslim God does not establish laws of nature and leave them to operate. He is personally involved in causing every natural event by a direct act of will. Thus, al-Ghazali insisted that when a ball of cotton is placed into a flame, the fire does not burn the cotton. Instead, “when fire and cotton are placed in contact, the cotton is burned directly by God rather than by the fire.”

If you think this is very old, Medieval history, consider that there was a controversy in the 1980s in Pakistan, when Islamists insisted that chemistry textbooks had to say that when hydrogen and oxygen are combined, then by the will of Allah, water is created—directly borrowing al-Ghazali’s formulation. The rejection of scientific laws and secular reason was codified in Islam long ago, and those who depart from this orthodoxy continue to be ostracized, as seen in Pakistan’s rejection of one of its most eminent physicists.

All of this has a lot of implications for how you deal with disagreement and whether you think religion is a subject that can be debated. The Byzantine emperor quoted by Benedict argues, “Whoever would lead someone to faith needs the ability to speak well and to reason properly, without violence and threats,” to which Benedict added: “The decisive statement in this argument against violent conversion is this: not to act in accordance with reason is contrary to God’s nature.” Whereas if reason is itself heretical, then why should anyone tolerate your arguments and philosophical debates?

Secular law versus Sharia law.

The differences between Islam and Christianity are not just about the laws of nature. They’re also about laws for man.

Christianity has its own religious law, laid down by Moses in the Old Testament, though much of it does not survive Christ’s revisions. But Christianity also has a long tradition of coexisting with secular systems of law. This comes from the Roman context, where there was an established, codified Roman system of law which Christianity did not seek to overthrow. This, as I understand it, is part of the significance of Christ’s admonition to “render unto Caesar that which is Caesar’s.” So the idea of religion as the source of law was not well-established under Christianity. Or to be more exact, religion is viewed as source of general moral principles, but there is plenty of room for debate on what those principles mean and how to translate them into specific laws.

By contrast, Islam recognizes no room for any law other than what was supposedly revealed to Mohammed, and that is the source of a whole lot of trouble. The explicit argument offered by Islamists against representative government is the complaint that laws voted on by the people are laws created by man, whereas God is the only one who can make law. Similarly, one of the main issues of contention in newly created governments across the Middle East—Afghanistan and Iraq, as well as Egypt, Tunisia, and Libya—was the question of whether Islam should be cited as the sole source of law. Then there is Saudi Arabia, where the Koran is the constitution.

But what is really telling is the concreteness of Islamic law. As it is usually interpreted, Sharia is not a set of general principles that leave room for individual judgment in their application. It is a set of extremely detailed, specific requirements and prohibitions. This is why we see Islamic clerics asked to issue “fatwas” on every triviality under the sun, from soccer to tomboys to Mickey Mouse, which can lead to some very weird results.

As British Islamist Anjem Choudary explains to us, “Islam does not mean peace but rather means submission to the commands of Allah alone. Therefore, Muslims do not believe in the concept of freedom of expression, as their speech and actions are determined by divine revelation and not based on people’s desires.” Note how total this is—everything is determined by revelation—and how little room it leaves for individual choice. So no wonder it is used as a license for unlimited coercion.

The concrete nature of Islamic law and its devaluation of individual judgment reflects a deeper aspect of the difference between Christianity and Islam.

Is it normal to struggle with faith?

Christianity has a tradition of being an introspective religion, one that is about plumbing the depths of one’s soul—and about struggling with one’s faith. In the Bible and in Christian lore, there is a long tradition of openly talking about struggles with doubt, the sense that faith is something that can be difficult to maintain, so that lapses or skepticism or a crisis of faith are understandable and to be tolerated. The put-upon Job debates with God. Even Jesus struggled with temptation and doubt in the Garden of Gethsemane as he faced the prospect of crucifixion. That’s why the typical piece of Christian “hate mail” I get is annoyingly non-hate-filled. They mostly tell me that they’re praying for me so I will one day see the light.

By contrast, Muslims widely accept a particularly literal version of what the Christian would call “salvation through works.” In its crudest version, this is the “die in jihad and get 72 virgins in paradise” outlook. Getting into heaven is less about reordering your soul or trying to introspect some greater meaning in your life—and more about punching a checklist of external actions, of being obedient to a long list of strictly enforced requirements and taboos.

The history of religion in America.

The final big difference between Islam and Christianity isn’t something that’s wrong with Islam, but rather something that happened uniquely in the West that influenced Christianity: the history of religion in America. From the beginning we had a profusion of different religious sects, many of which had come here seeking freedom from persecution. So from early on, at least from Roger Williams, American religious leaders were deeply involved in developing the ideology of religious freedom. While Enlightenment ideas had a wide influence in America, demands for religious freedom did not come primarily from anti-clerical types who wanted to abolish religion. Instead, religious freedom was literally preached from the pulpit, which is why it so naturally made it into our founding documents.

That’s only one aspect of Christianity in the West, of course, but it has had a global influence on the religion and its approach to liberty.

I have painted with broad strokes, and there are some who will no doubt come back to me citing Muslim leaders who espouse better views, as no doubt you could go out and find Christians with much worse views.

And of course, many of those who kill in the name of Islam don’t even know this history. One of my favorite stories is about British jihadists who headed off to join ISIS in Syria after buying a copy of the book Islam for Dummies. These guys aren’t following the narrow doctrinal disputes. What they absorb is an overall sense of what the religion means and how it is to be practiced.

If you add up all of these things, you see what an explosive mix you get from Islam: the expectation that religion dictates everything and that their religion ought to be totally dominant here in this world, combined with the notion that religion is not open to reason and leaves no room for doubt, questioning, or debate.

Religious ideas can be, and often are, recombined and reinterpreted in more or less benevolent ways. There will always be a tension between faith and reason; the concept of service to others can be used to demand service to the state; the concept of man’s sinfulness and imperfection can be interpreted to mean that the perfect religious society cannot be imposed on earth—or that humans can’t be trusted with freedom, so the state needs to curb our vicious impulses. Certainly, the recent comments by Pope Francis on the Charlie Hebdo attack should make us wonder how committed he is to the principle of freedom of speech.

But this should make us appreciate all the more the way in which, after centuries of contentious and often bloody history, our culture’s dominant faith has settled into a more benevolent and liberal form.

We can hope that Islam will do the same. But in terms of their history and doctrines, they still have a long way to go—and I’m afraid they still have some of those contentious and bloody centuries ahead of them.

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