One of the puzzling things about the Pope’s visit has been the media’s mantra-like repitition of the fact that Benedict believes that Catholicism is the “one true faith,” as though this was something odd or eccentric. The obvious and snarky response to this astonished observation is that, well, he is the Pope.
But more to the point, I bet if you actually asked Benedict if Catholicism is the one true faith he would say something a great deal more nuanced than that. Since, as anyone who bothered to look into it would know, one of the big concerns of all the major Christian denominations over the last, say, 50 years or so has been interfaith relations (both intra-Christian ecumenicism and relationships with non-Christian religions), you might think that Christian thinkers have given some thought to this issue.
And you’d be right! Indeed, right there in the Catechism of the Catholic Church itself you can read that
The Catholic Church recognizes in other religions that search, among shadows and images, for the God who is unknown yet near since he gives life and breath and all things and wants all men to be saved. Thus, the Church considers all goodness and truth found in these religions as “a preparation for the Gospel and given by him who enlightens all men that they may at length have life.” (843; the quoted portion is from Lumen Gentium)
Like many Protestant churches, the Catholic Church recognizes that there is truth in other religions. To speak unqualifiedly of the “one true religion,” then, would be a mistake.
Which doesn’t mean that Catholics and other Christians don’t think that Christianity contains important (indeed the most important) truths that other religions see only dimly, if at all. Above all, of course, it’s the revelation of God in Jesus that Christians see as the definitive disclosure of God’s will and purposes for the redemption of creation. If adherents to other religions deny that Jesus is the Son of God, then Christians, pretty much by definition, think that they deny an important truth. Likewise, faithful Muslims and Jews think that Christians get an important truth about God badly wrong when they assert that God became incarnate in a human being. These are real differences of belief about the divine nature: there’s no virtue in trying to believe a contradiction.
But it’s a staple of much writing about religion in the popular media that religious belief simply can’t be a matter of truth, but is instead a matter of preference or, at most, an expression of an utterly ineffable spiritual experience. But this position, ironically, assumes a superior vantage point on the truth of the matter than that occupied by sincere religious believers themselves. If I say that all religious “truths” are merely preferences or symbols of a transcendent reality, then I’m claiming to have access to the truth about the matter that bypasses these religious traditions, a “god’s-eye view” of the situation. In saying that we’re completely incapable of speaking truthfully about ultimate reality, I’m in fact making a claim about the nature of ultimate reality (namely, that it resists truthful description), and so fall into self-contradiction.
It turns out, then, that the Pope’s position is actually the more humble one. He adheres firmly to the truth as he sees it by his lights, but also recognizes that other religions participate, to greater or lesser degrees, in that truth.
This isn’t to say, moreover, that some apparent conflicts between religions won’t turn out to vanish upon inspection. In many cases claims that seem incompatible on their face might, when properly understood, turn out not to be in conflict after all. For instance, it’s possible that claims made by certain Hindus about the impersonal nature of the divine which seem to contradict Christian views could turn out to be simply speaking about a different aspect of the divine being and ultimately be compatible with Christian belief (I’m not saying that’s necessarily the case, but it could be). This is something that can really only be discovered in talking with people of other faiths and trying to understand what they believe, not by sweeping all truth claims under the carpet of relativism.