Here I offer some basic guidance about how people of different faiths can engage with each other in meaningful and productive ways. This advice is the product of 36 years of interfaith work, culminating in my present job as Associate Dean of the Office of Religious Life at the University of Southern California.
1) The world's religions are different from each other. That ought to go without saying, but there are many people who believe that each religion is just a different path up the same mountain, or that they are different languages to express the same experiences. They can be forgiven for this, because indeed there are threads and themes that look familiar across the lines of faith. My colleague at Stanford, Robert Gregg, former Dean of Memorial Church, once wisely said that the world's religions are many paths up many different mountains. But when you get to the top of any of the mountains, you can admire a beautiful mountain range. In interfaith conversations, it's a lot safer and also a lot more interesting and productive to presume that the religions of others are pretty different than one's own. Then, when you discover striking similarities, you can be surprised pleasantly. But we do best to remember that lurking even in the similarities there may be really interesting differences. For instance, prayer beads show up in the devotional practices of Hindus, Buddhists, Christians, and Muslims. The Buddhists learned it from the Hindus, the Muslims copied the Hindus and the Buddhists, and the Christians copied the Muslims. But in each tradition, the devotee is doing something inwardly different than the others when they finger the beads in roughly the same outward ways.
2) The differences between religions are different. The difference between Hinduism and Islam is not analogous to the difference between Christianity and Judaism. Furthermore, these faiths have substantially different endogenous definitions of religion. Judaism as a religion is quite different than Christianity as a religion. For one thing, Judaism has an intrinsic ethnic identity that Christianity lacks. The failure to account for the differences between the differences results in deep misunderstandings in interfaith contexts. An example is the website "Belief.net", one of the earliest attempts at interfaith engagement online. The very title of the website reflects a Protestant Christian bias. For evangelical Christianity, religion is defined first and foremost by belief. But many other faiths are defined more by rituals and practices than by doctrinal assertions.
3) Religions, and sects of religions, have different ways of understanding religious differences. But these differences don't necessarily impede interfaith engagement. Diana Eck of the Harvard Pluralism Project defines three general ways that religions relate to each other. Pluralism is the idea that other religions may be as good for others as mine is for me. Inclusivism she defines as the assumption that other religions may have truth and value worthy of engaging, but whatever is good in them is but a lesser reflection of the ultimate, authoritative good of my own tradition. Eck defines exclusivism as the assumption that other religions are wrong at best and evil at worst, and that my faith is the only true one. Some folks believe you have to be a pluralist in order to have substantial relationships with people of other faiths. They assume that interfaith engagement is primarily a sport for theological liberals like myself. But I have witnessed close working relationships and deep friendships between people who hold exclusivist views within their different faiths. Sometimes, conservatives of differing traditions get along better with each other than they do with their liberal, pluralistic co-religionists. One of the favored places for conservative Middle Eastern Sunni Muslims to send their kids to college in America is Brigham Young University in Utah, a Mormon school. I do think that pluralism makes more room for appreciating the faiths of others than does inclusivism or exclusivism. But these latter two approaches still can allow for very rich interfaith conversations.
4) Different issues make for surprising interfaith bedfellows! Understanding the nuances of different faith perspectives on social issues is important for those who want to promote interfaith cooperation, to seek common ground where possible, and make room for disagreement where possible. An important example is "religious freedom". In America today, the theologically progressive branches of Christianity, Judaism, and some other faiths tend not to perceive any threat to the free exercise of their faiths. Meanwhile, some of the more conservative manifestations, particularly in Christianity, feel that their religious freedom is under attack as social norms and laws have changed.. These conservative religious groups define "religious freedom" to allow their organizations and their followers to discriminate against people who violate their faith-based norms. They believe that religion should not just be freely exercised, but also given a privileged status by the government to influence the wider society. But some faith communities that share this view may disagree about other definitions of religious freedom. For instance, they may agree that a company owned by a person whose religion forbade birth control should not have to offer employees health insurance coverage that included contraception. But they might disagree about churches keeping their tax exempt status if their preachers endorsed political candidates from the pulpit. Understanding the historical and theological reasons for these differing views will help greatly in promoting interfaith engagement.
5) It's good to know something about the world's religions: at least enough to know just how much you don't know! Most of the numerically significant religions have enormous troves of texts and rituals and traditions. I have spent my entire life studying my own tradition, Christianity, and the more I learn, the more I discover there is to learn. The older I get, the more boggled I am by its depth and breadth. I can only presume that this is the case for the other faiths, too. I've studied many of them in some depth, but only enough to be aware of the depth of my ignorance of them. Effective interfaith leadership requires curiosity and humility. It requires the constant assumption that regardless of your level of education in world religions, there is so very much more to know that could affect your relationships with people of other faiths. Ask questions, and then ask more questions based on the answers.
6) In America today, "innerfaith" exploration is part of interfaith engagement. The trend in religion in the US is toward increasing heterodoxy. Catholics are doing yoga. Evangelicals are going to tarot card readings. Jews have been practicing Zen meditation for decades. Even people who profess strong traditional religious identities are engaging in the practices of other religions and cultures, mashing them up as they follow their own personal spiritual paths. Just because somebody says they are a Zoroastrian, and you happen to know a lot about that tradition, that doesn't mean you know what that individual believes or practices. With enormous amounts of religious information now accessible on the internet, people are trending away from reliance on their pastors and priests for authoritative knowledge about matters spiritual, and are claiming their own authority. Some folks who get involved in interfaith dialogues have no firm or fixed religious identity, but are taking their own "innerfaith" journeys. They can cause frustration for those who want to engage with serious practitioners of different historic traditions. But as the number of religiously unaffiliated people grows rapidly, we need to make room at the interfaith table for them. We need to make room for overt atheists, too. We need to ask questions. Where and how do you find support from other people for your spiritual journey? How do you experience spirituality, and what practices do you employ to evoke or express it?
7) You can grow in your own faith tradition through deep exposure to other traditions. One reason to get involved in interfaith work is to look more critically at your own faith, take it more seriously, and become more curious about it. This has been my own experience. Learning and practicing Buddhist meditation methods led me to explore the rich meditative and contemplative mystical traditions of my Christian heritage. Learning about other faiths from their practitioners has heightened my interest in their similarities and differences with my faith. Any risk of temptation to switch religions is outweighed by the benefit of going deeper in one's faith as a consequence of interfaith dialogue.