When people think of religions, they tend to turn to of the big five: Christianity, Islam, Judaism, Hinduism, and Buddhism. Although these are the most popular religions in the world, they are a minuscule sample of the thousands of religions that have existed over humanity’s history, and a small slice even of religions that exist today.
Despite the obvious differences between the big five, there are some deep similarities. In particular, the big five tend to focus on communication of important ideas through repeated exposure to scripture and speech.
The emphasis on language is not universal. For many religions, ritual play the major role in teaching people what the religion is all about. For example, many Melanesian religions have what are appropriately called “rites of terror.” These coming-of-age rituals often involve burning, bleeding, months of isolation, beatings in the middle of the night by people in costume, and food, water, and sensory deprivation. Many anthropologists who have studied these rites tell us that the very experience of going through them creates a lifelong, vivid, emotionally-charged memory that is crucial to understanding and belonging to the religion. Often there is no interpretation provided, and in some Melanesian fertility cults it is taboo to even discuss what happened during the ritual; in pre-colonial times such discussion was punishable by death. Each person goes through their own personal revelations brought about by the ritual, rather than reading or hearing about others’ revelations. Anthropologist Harvey Whitehouse calls this kind of religious transmission “imagistic”; it relies on the episodic memory of an experience that can’t be put into words. Because it is so powerful and emotional, it only needs to happen once.
Compare this with reading scripture or listening to a sermon, which is repetitive, based on language, interpreted by experts, and not particularly emotional. This kind of transmission is called “doctrinal.” Because it is language-based, complex, and low-affect, it is easily forgotten and requires constant repetition to be remembered. As such it uses semantic memory system rather than episodic. For example, Jews might feel they understand the lesson of the story of Abraham nearly sacrificing his son, Isaac, but not remember when they learned it.