There are two main kinds of religious pluralism. One is good and one is intellectually bankrupt.
Good pluralism: Numerous distinct ethnic, religious, or cultural groups are present and tolerated within a society.
Bad pluralism: All religions are true and equally valid paths to God.
Pluralism can be a good thing if it means we should tolerate the beliefs of others. Jesus, who was God in flesh, didn’t force anyone to convert. So why should we think that we can?
Christianity should flourish in a society with good pluralism, as the Gospel can be shared freely and there isn’t pressure to fake one’s beliefs. Sadly, we often get complacent in such atmospheres and Christianity spreads just as well or better in times of persecution. It tends to weed out false believers and teachers more effectively.
Of course, there are some truths in each religion, but there are irreconcilable differences in their essential truth claims regarding the nature of God, the path to salvation, their view of Jesus, etc.
Here are some examples:
One of the following is possible when we die, but under no circumstance could more than one be possible:
- Reincarnation (Hinduism, New Age)
- Complete nothingness (Atheism)
- One death then judgment by God (Christianity, Islam, others)
Jesus was either the Messiah (Christianity) or He was not the Messiah (Judaism and others), but He cannot be both the Messiah and not the Messiah.
God either doesn’t exist (Atheism), He exists and is personal (Christianity) or He exists and is impersonal (Hinduism).
Jesus either died on the cross (Christianity) or He didn’t (Islam). The Koran repeatedly claims that Jesus did not die on the cross (Sura 4:157-158). What evidence does Islam offer? One guy with a vision over 500 years after the fact. That is not what we base history upon, especially when scholars of the first century — whether Christians or not — agree that a real person named Jesus died on a Roman cross.
God either revealed himself to us (many religions) or he didn’t (Atheism, Agnosticism).
Jesus is the eternally existent God (Christianity) or He isn’t (everything else, including the Mormon and Jehovah’s Witness). In fact, in Islam it is an unforgivable sin to claim that Jesus is God, so there is no way to reconcile Christianity and Islam.
Some people hold the view that God will be whatever you conceive him to be in this life. That is one of the most bizarre religious views I have heard. I’m not sure how they came to the conclusion that every human gets a designer god and that at death it would be just as one wished.
Consider the view of Mahatma Gandhi and Hinduism in general:
After long study and experience, I have come to the conclusion that  all religions are true;  all religions have some error in them;  all religions are almost as dear to me as my own Hinduism, in as much as all human beings should be as dear to one as one’s own close relatives. My own veneration for other faiths is the same as that for my own faith; therefore no thought of conversion is possible. (Mahatma Gandhi, All Men Are Brothers: Life and Thoughts of Mahatma Gandhi as told in his own words, Paris, UNESCO 1958, p 60.)
Yet the exclusive claims of Christianity prove Gandhi’s worldview (that of Hinduism) to be false. Among other things, the Bible claims at least one hundred times that Jesus is the only way to salvation. It also commands us not to worship idols and that we die once and then face judgment (it does not hold to reincarnation). Those are key elements of the Hindu faith. So if Hinduism is true then Christianity cannot be true. But if Hinduism is correct in stating that all religions are true, then Christianity must be true. But Christianity claims to be the one true path, so if it is true then Hinduism is not.
Also, Hinduism claims that Christianity is true, so if Christianity is false then so is Hinduism. Either way, the logic of Gandhi and Hinduism collapses on itself.
When I share the Gospel with people I do so as respectfully as possible. But I always try to work in examples like the above to highlight that under no circumstances can we both be right about the nature of God and salvation.
I used to hold the position of religious pluralism. We studied world religions about 15 years ago in an Adult Sunday School class and, sadly, didn’t dig very deep (I was attending church but not really a believer . . . at best I was “saved and confused”). Most of us walked away thinking the religions were “all pretty much the same” and with no incentive to go out and make a case for Christianity.
So why did I – and so many people today, including Christians – embrace bad pluralism? I think it is typically out of a lack of clear thinking on the topic. When you examine the essentials of these faiths it is not that hard to show how they are irreconcilable.
Political correctness and fear contribute as well. It is easy to deny the exclusivity of Jesus (or the truth claims of whatever faith one follows) if one wants to avoid controversy. But as unpopular as it is to make truth claims, it is really a rather logical thing to do. The one claiming all religions are true needs to back up that claim with their evidence and logic. Just rattle off a list of religions, sects and cults and ask why they are all true. Just be careful saying things like, “Hinduism has a lot of sects.” If you say it too quickly people will have surprised looks on their faces.
Sheer laziness is another factor. Knowing enough about one’s faith to defend it in the marketplace of ideas is hard work. Religious pluralism is a great excuse not to evangelize.
I expect many non-Christians to say that all paths lead to God, but it really bothers me when Christians do so. They should meditate on this passage, among others:
Galatians 1:8-9 But even if we or an angel from heaven should preach a gospel other than the one we preached to you, let him be eternally condemned! As we have already said, so now I say again: If anybody is preaching to you a gospel other than what you accepted, let him be eternally condemned!