When it comes to religion and our understanding of what it is; we can take the academic viewpoint that what is documented is also what is truth; and so if it isn't documented, then it cannot be true. The religious viewpoint is that: what the believer believes—is what is true for the believer; in some cases the believer may experience their belief to be objective truth, and that is of course also a belief to be considered.
For ancient religions, since long dead and buried, the academic viewpoint should for natural reasons be very humble; since the only thing we can say with certainty is that we don't know with certainty. Most of the most relevant documentation has been systematically destroyed, and only that which would comply with the, at the time present, doctrine would have been saved—in those cases anything were actually documented; many cults have taught knowledge and understanding entirely through personal experience, and not by reading books. In other words, only one who had been initiated into the cult would understand it, and then only those with the highest grade of initiation would understand it completely. A secretive mystery-oriented religion could only be understood at all by those initiated into a similar religion with similar views; though we cannot know if any similarities are real by reading documentation of second hand observations.
Reconstructing religious practices for personal religious experience may of course be fruitful, even though the results vary perhaps, in the case of success it proves the method to be effective and authentic. It may however not prove how it was practised or experienced historically.
Modern and living religions may more easily be understood by becoming initiated. However, unless we actually have practised a religion in length and depth, with sincerity and conviction; reading about it may at best simply be entertaining, but could have no real academic value at all.
Speculation about ancient religions is naturally fascinating; a lot of ideas about how it was to have had this or that faith during this or that period of time can stimulate the imagination in many ways, and have done so to many people. Reading the Bible may stimulate the imagination about what Christianity is about, it may awaken some thoughts; but unless there is a personal experience of having been truly baptised, having been in communion with God, Christ and the Holy Ghost, and found the Bible to be Holy: speaking about Christianity can only ever be in terms of mockery or at best ignorance; and it is the same with all other religion. Individuals with religious experience may find that other individuals of other faiths perhaps have had similar experiences, have seen or felt similar things, but unless those individuals express and agree to have had the same experience, it is but an assumption.
The human experience of life, nature and the soul may be considered universal, so we may say that a deep personal understanding of life and the soul grants a better understanding of religious dogma. This viewpoint would be perhaps better than the academic one; e.g. someone who have meditated intuitively for a long period of time may have reached the same levels of consciousness as those trained in meditation in a monastery, and thus having achieved the same experiences. It would only be natural that such a person would better understand religion than someone having read a lot of books about it; but not necessarily, since the religion may also contain the collective effort of meditation of thousands of adepts during thousands of years; of adepts having reached much deeper levels of consciousness because they were very gifted or better trained.
Living initiatory traditions teach the knowledge and understanding of the tradition so that it ensures new adepts to have reached a certain level of understanding before granting the initiation. This creates an unbroken chain of knowledge from the creation of the tradition—and commonly long before that because religious traditions usually are based on even older traditions.
Considering this, talking about religious facts, in particular when it comes to historical facts, would seem a bit too speculative for any other reasons than a personal religious understanding or that it is entertaining to think about. Unless actually having the real knowledge, it would be only vain and pretentious to claim such a thing. Also, having that real knowledge means keeping it secret to all but those ready for receiving it, because it is sacred; not for the sake of keeping it secret, but to avoid it becoming profaned or misunderstood because of lacking spiritual maturity. For example, publishing the heavy material of the sacred Golden Dawn would not be a problem since only someone with great dedication would read it, and it is designed to be practised and understood through the practice; and only someone with true initiation can claim to have this understanding. So the secret is not in the documentation, but in the experience of the rituals—which is profound.
