I would postulate that the root of every significant world religion is a set of assertions of absolute truth...These form essential tenets...Each religion then has a particular mass of secondary attributes; rules, regulations, dogmas, scriptures, cultural origins, etc...
See, I don't think of the belief part as
the sole primary attribute. Practices, rituals, and social interactivity aren't secondary attributes, but at least co-equal with belief and mythology. And in some religions, practice is considered to be of primary importance. In ethnic religions, the thing that marks a person as part of the culture's religion is their
participation in rituals and customs relating to it. Belief in the relevant deities or spirits is
strongly implied, and assumed on the part of the participants. But it isn't, strictly speaking,
necessary in many cases. Religion in such contexts is structurally a community exercise in social cohesion--even though the participants might think of it differently. This standpoint is most clearly elucidated in historical Roman religion, when we see several authors who were personally skeptical of the gods nonetheless noting the importance of religion in social life and stability. But you can find similar ideas from writers based in other indigenous religious traditions.
I again come to the point that Christianity has (for understandable reasons) become the standardized model of religion in the minds of most Westerners. But Christianity's
strong emphasis on faith has rather overshadowed other aspects that tend to be emphasised in most other religions around the world. Christianity's strongly faith-based approach is atypical, and does not make for a good baseline model.
But, in favour to your point, the three largest individual religions are the ones that postulate some absolute truth, asserted it vigorously, and evangelized over the course of centuries: Christianity, Islam, and Buddhism. I would still say that they are rather atypical, though, if we are evaluating (as I have been doing) religions on a case-by-case basis rather than proportional.
I guess I largely agree, although I'd discard the "sacred" part. I'd say religion is nothing more than a social construct.
Even if you do not believe that a particular thing is "sacred", the people participating in a given religion
do. And it is
their perspective that matters in defining the structure of the religion in question. The dichotomy between the Sacred and the Profane is an essential part of the study of comparative religion and comparative mythology. It is something you find in virtually every religion across the world, and is the basis of what differentiates religious practice and belief from cultural custom and folklore.
How do you know the entity is who you think it is? Apollo for example.
From my perspective, I see it as a matter of education and preceding knowledge. I know a considerable amount about the Greek gods, as depicted in mythology and as historically represented in cult. If I were to encounter an entity claiming to be Apollo, I would try to discern if it exhibited the personality traits and other qualities associated with Apollo by the ancient Greeks and Romans before I fully believed it. But even then, it's possible to be deceived. To an extent, that is a matter of faith; but it's no less so than trusting one's senses when trying to observe and study the natural world or human behaviour.