When I was a new believer seeking reasons for my faith, I inhaled the writings of Christian apologists such as C.S. Lewis and Josh McDowell. The way my unsophisticated mind summarized much of their material was something along the lines of, "Christianity is different from all other world religions because it is the only one in which we don't have to earn our way to heaven, because salvation is by faith, not by works."

Boston University's Stephen Prothero no doubt would have challenged my simple formula on a number of levels, such as the obvious one that Christianity includes a prominent place for works, and other religions also have faith—that is, trust—in something at least. One point we would have wholeheartedly agreed on, however, is that Christianity indeed differs from all other faiths.

But Prothero would have gone further: all the world religions, in fact, differ one from another. Prothero dismisses as sentimental nonsense the theories of many other religion scholars, such as Huston Smith, that the various world religions, though different from one another in outward ephemera, share at their core the same spirit, that they are "different paths up the same mountain."

These hopeful but ungrounded views, Prothero says, result from the influence of religious pluralism, a reluctance to argue, and a desire to homogenize religion in order to dampen violent fanaticism such as the kind that brought down the Twin Towers: "One purpose of the 'all religions are one' mantra is to stop this fighting and this killing."

In a previous book, Religious Literacy, Prothero showed how clueless many Americans are about religion—a finding confirmed by a survey last fall from the Pew Research Center: most Americans flunked the quiz on Bible knowledge, world religions, and the role of faith in public life. In his latest project, God Is Not One: The Eight Rival Religions That Rule the World—and Why Their Differences Matter, Prothero seeks to overcome our ignorance with an armchair guide to the major world religions, a job he undertakes with a certain sense of urgency: "naïve theological groupthink," he argues, has made the planet we share more dangerous. I wonder, however, whether an informed awareness of our differences really makes us less likely to fight. Maybe it does, maybe it doesn't. It could even make conflict more likely. I, for one, seriously doubt that the Islamists seeking to overthrow the West will be pacified by reading this thoughtful and engaging volume.

While pointing to salient religious differences, Prothero freely acknowledges that all religions agree there is something wrong with the world, that it is somehow "out of balance." But they disagree both on the diagnosis and on the cure. For example, Prothero would have disputed my belief that followers of other faiths are seeking salvation of the kind held out by Christianity—that is, a spiritual deliverance from sin, ultimately leading to the bliss of heaven and avoidance of the other place. Prothero insists that most religious adherents—at least those outside Christianity and Islam—aren't even looking for heaven. "The world's religions are clearly related," he writes, "but they are more like second cousins than identical twins. They do not teach the same doctrines. They do not perform the same rituals. And they do not share the same goals." Amen.

That being so, he suggests, each religion must be understood according to its own ground rules, much as the goal of baseball is to score runs, the aim of football is to score points, and the focus of hockey is to score goals. We all want to score, but we all want to score different things; it would be absurd to criticize a baseball team for failing to score goals.

In perhaps the most helpful contribution of God Is Not One, Prothero provides a template to discern the differences. He says each global faith points to a key problem confronting the human race and the world (in Christianity, sin), proffers a solution (in Christianity, salvation), presents a technique toward that end (in Christianity, a combination of faith and good works), and provides exemplars who have lived out the faith (in Christianity, saints, or ordinary Christians). This template, while necessarily oversimplified, is a great tool that allows us to quickly grasp the different essences of the world religions. Such an approach could aid missionaries in exegeting other faiths, with a view to contextualizing the Christian message in terms that connect. But Prothero, who describes himself as "religiously confused," never takes the next step up the mountain to ask the ontological question about each faith: Is it true? Instead, he asks the practical question: Does it work?

Prothero has given us a factual, largely irenic look at the eight most influential faith systems (though followers of Sikhism, Jainism, and Shinto—which are left out—might disagree). He provides thought-provoking essays on Islam, Christianity, Confucianism, Hinduism, Buddhism, Yoruba Religion (an interesting nod to a global form of animism), Judaism, and Daoism, with a brief discussion of atheism.

Laudably, he provides accounts "to which adherents can say 'Amen'" even as he wrestles "with the fact that in writing about any religion, one is treading on dreams." Prothero helps us begin to see other faiths the way their followers see them—no small thing. There are no hatchet jobs here, but, then again, the book becomes a little bland as it tries to give each faith the benefit of the doubt.

In the case of Islam, for instance, Prothero is quick to explain away problems (he summarizes the conflict between moderate Islam and violent Islamists as "a clash between Muslims who believe that Islamic tradition means what it says when it comes to not killing women and children, and those who do not"). He devotes six of the chapter's 40 pages to Islam's fascinating but numerically unrepresentative tradition of mysticism, which he evidently (and understandably) prefers to the strictures of Wahhabism.

Prothero at times puts a positive spin on some "difficult teachings" of the non-Christian faiths. This includes the Buddhist doctrine of emptiness, which says we have no permanent distinctiveness (or difference) from anyone or anything else. He reinterprets it as a "teaching of freedom," because it "liberates us from enslavement to people, judgments, objects, and ideas, including the person of Buddha and the institutions of Buddhism itself." Of course, so does Christianity, but in a completely different way!

And why does Prothero feel constrained to present all the religions positively, anyway? (One wonders what he would have done with ancient Baal worship.) Why must these different religions all be viewed optimistically? Isn't optimism a distinctly Western value? The approach here seems very American.

I wonder if a fair and comprehensive understanding of the various religions is even possible if the writer, an acknowledged sympathetic outsider to the faiths, cannot or will not acknowledge his own biases? On what evaluative ground does he stand? It's hard to tell. As a non-participant, the BU professor of religion has tried to give us the good and bad points of these faiths—at least by his lights. Still, I am reminded of the Middle Eastern saying, "Keep your friends close and your enemies closer." How close can Prothero get to the religions as a friend to all of them?

Unfortunately, often it seems as if the reader is left to discern not whether a faith is good or bad, but simply what Prothero likes about it and what he doesn't. Prothero says that, for example, the Qur'an's "fear-mongering" on the torments of hell as an inducement to become a Muslim produced in him a certain "disquiet."

Is there more to a religion than how it makes us feel? Our feelings, after all, are determined to a large extent by our upbringing and culture. Yes, most Muslims will feel the need to submit to Allah, because that is all they've heard about. But does Prothero's disquiet about hell tell us something substantive about the reality (or not) of the afterlife, or about Prothero?

You can only learn so much by peering through the stained-glass window. In the end, there simply is no substitute for walking in the door, sitting down, picking up your fork, and taking part in the banquet. As the biblical invitation wisely says: "Taste and see that the Lord is good."

And at some point, we must face the question of truth. As Jesus asked, "Who do you say that I am?" We could put the same query in the mouths of the other founders of the world's great faiths: Confucius, Muhammad, and Siddhartha Gautama among them. We have to decide because, as my former pastor Kent Hughes said, "It's only life or death!" Even not deciding is a decision. So how do we get beyond our own preferences and find out which religion to follow?

Certainly we can start by asking how well each world religion fulfills its own criteria, which Prothero does well. For if it cannot do even that, then we are well advised to look elsewhere. As Jesus said without fear of contradiction, "A tree is known by its fruit." So do the sincere followers of Allah submit to the Divine better than the rest of us? Have faithful Christians experienced actual deliverance from sin? Are Hindus more devoted?

A second way to evaluate the fruit is to see how these religions have affected history, society, and culture. Evaluating the influence of each faith, Prothero makes a decent start here, but there is much more to be said. Which religion, in a word, has done the most good? For example, while Prothero labels atheism "the way of reason," he will get an argument from Christians.

It was Rodney Stark, after all, who wrote The Victory of Reason and observed, "The success of the West, including the rise of science, rested entirely on religious foundations, and the people who brought it about were devout Christians." Question: Which religion led to the kinds of universities in which professors such as Prothero can pursue their vocations? I think Prothero knows the answer.

And which one has done the best job, say, in caring for the poor? "If you want to help the homeless, you will likely find the Christian Social Gospel more useful than Hindu notions of caste," Prothero says. "If you want to find techniques for quieting the mind through bodily exercises, you will likely find Hindu yogis more useful than Christian saints."

Useful? Which vision—quieting the mind or helping the poor—is ultimately better? Religion is all about making choices, but Prothero primly steps away at this point. He shows us the differences between faith systems, but not which ones lead us to the true, the beautiful, and the good. His even-handedness makes it seem that it doesn't really matter which faith you choose, because the differences, despite the book's sensationalistic subtitle, don't really matter. But isn't this a strange place for a book focusing on religious differences to land?

Third, we should be willing to ask followers of other faiths to try on ours, or to try theirs on ourselves. This is the test of experience, tasting the bread and the wine at the banquet. Prothero rightly notes that the great faiths don't exist in pristine isolation, under glass. They interact, learn from, correct, and rebuke one another in the real world, across the barriers of culture, geography, and time. This sometimes involves what critics call "proselytism," as if one faith is no better than another and that attempting to sway someone to adopt your own is simply gauche.

But doesn't religious pluralism require religious freedom? (Not all faiths, by the way, equally esteem this basic human right, which came from somewhere, after all.) And when people exercise this right, the results can sometimes upset the religious apple cart. It is well known in Christian missionary circles, for example, that many Muslims and Jews have found in the risen Christ the answers to questions their former faiths only hint at, and the fulfillment of deep longings that their old religions can never plumb.

Their God-given freedom to choose has sometimes caused friction, as have the choices of some Christians to embrace Islam or Judaism. Religion, after all, is much more than an academic exercise, a comparison of similarities and differences on the path up the pluralistic mountain.

In fact, to be ultimately useful, religion must become an upward-looking search for the Way, the Truth, and the Life. Because, as Prothero would heartily agree, the study of religion is not only an academic discipline. It is a personal one, too.

Stan Guthrie, a Christianity Today editor at large, is author of All That Jesus Asks: How His Questions Can Teach and Transform Us (Baker Books). He blogs at stanguthrie.com.

Copyright © 2011 by the author or Christianity Today/Books & Culture magazine.
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