How does Religion work?
I understand why game systems generally seek to avoid such a sensitive and controversial topic. J.R.R. Tolkien faced this situation when he wrote Lord of the Rings and the Hobbit. While religion is present in Middle Earth (Eru, the Valar, the Maiar, etc.), it is based around creation stories and mythology (the Silmarillion). While introducing a fantasy, non-Christian religion, Tolkein stayed away from developing organized religions (temples, clergy, rituals, worship) for both good and evil.
In the 1970s, Gary Gygax and TSR initially embraced religious diversity and pluralism through the publication of Dieties and Demigods which offered a simplified but handy guide to our world’s ancient religions. It avoided the religions that are still practised around the world and instead mixed in a variety of fantasy religions. The evil faiths were reserved for the Hells and the Abyss in the form of devils and demons. But amidst the “Satanic Panic” of the 1980s and the revival of religious fundamentalism in North America, D&D backed off its initial incursion into religion (most evident in the development of new more politically-correct names such as Tanar’ri and Baatezu).
A second way D&D seeks to avoid religious controversy is by handling religious power in the same way it handles “magic”. As a result, both wizards and clerics have “spells” and they are both considered magic.
The Game handles religion in a different way than most game systems. In essence, religion is treated much the same as it is in the real world.
My world includes every pre-gun powder society that exists in the real world. Therefore, all of these religions also exist. This includes the polytheistic religions of the ancient world (Greece, Babylon, Japanese, Celtic, Norse, Mayan, etc.) but also the faiths that are still practised (Indigenous, African, Hinduism, Buddhism, and yes, even Christianity and Islam). Therefore, characters can be a Christian priest from Briton or an Islamic Iman from Arabia.
Even though I faced scrutiny from my own Christian fundamentalist community when I first created The Game in the early 1980s, I do not shy away from presenting evil religions in all their fiendish hellishness. Devils, demons, Hell, and the Abyss exist as sure as does God(s), Angels, and Heaven (in its many forms).
Nor do I shy away from having religious power as a separate force from magic. In my world, the two are in no way the same thing. “Prayers” are different from “Spells”. While I use the vast majority of spell descriptions from D&D, I do not use its clerical or druid spells. I find these descriptions so generic and with no real basis in the distinct religions from which they are being drawn. Instead, The Game has produced “Prayer Books” for many religions.
One of the main advantages of using our real world religions in The Game is the amount of detail characters can draw upon. The amount of information and detail on theology, texts, rituals and ceremonies, symbols, garb, etc. provides so much fodder for character development. Imagine that your character is a priest of Zeus and the amount of information now available online for you to employ. While I employ fantasy religions as well (for example the faiths of the Elves, Dwarves, Gnomes, Hobbits, Drow, Orcs, etc. from Forgotten Realms), the amount of necessary detail is substantially lacking and should be further developed.
The wide range of religious faiths in The Game often leads new players to ask a fundamental question. Many of these religions are incompatible with each other. How can polytheistic and monotheistic religions exist alongside each other? How can a character attached to a religion that believes fundamentally in one God adventure alongside characters who believe in many Gods? The answer is simple. They can exist in the same way they exist in the real world.
The fundamental point here is that religion remains a mystery. No one knows for certain what lies beyond the material world. No one can say for certain (other than through belief) whether God(s) exist and in what form. There is only spirituality and faith.