I agree with most of your last post. But a few things I don't agree with:
Mickiana said:
The ethic that is the basis of all religions is "Do unto others as you would have done unto yourself." I see all religions, at least in their origins, as an attempt to understand the truth. All the prophets of the various religions saw it as their mission to help others gain this understanding. As institutions run by fallible humans, religions become something other than a vehicle for the truth.
I've always believed that the primary purpose of religion was to explain the afterlife.
Yes, most religions do follow the ethic you mentioned, but not all do.
Actually, let me rephrase that: most religions expect you to follow the ethic you mentioned.
Islam/Christianity/Judaisism all teach this ethic (the Golden Rule if you will), but that isn't the main purpose of the religion. Christians want to save others by converting them and getting them to allow Christ "into their heart". Muslims and Jews want to do the right thing and live a good life.
However, in practice, few followers of any of the three religions actually follow the Golden Rule. Jihads and Crusades come to mind.
But, the followers all share the "salvation" factor. All do what is neccessary to reach paradise in the way they are told.
In less organized religions, the faith seems to be a way of explaining the world, and not salvation. Again, the Golden Rule is rarely applied here and, unlike those above, is rarely taught. Tribal religions and mythological religions teach that fighting is neccessary and basically tells them to go screw their fellow men. After all, their life doesn't matter.
But, their religion tells them how the world was created, why certain animals are the way they are, etc. And usually, it tells them that their position in the Afterlife depends on their life here. In fact, Norse mythology told that the only way to reach the Warrior heaven of Valhalla was by dying in combat.
So, I believe that religion's main purpose is to explain life and the Afterlife.
Mickiana said:
Now, the Big Bang. This is just an idea, mind you, but I suspect that the universe was always here, without beginning or end, that it is infinitely large and that the Big Bang was just a local event, judging by the remnant evidence that we currently observe through our very large telescopes and so was not the beginning of the universe. That's pretty well it. Tell me what you think.
I have to disagree here.
To me, the Big Bang theory, which there is much evidence for, is one of the greatest proponents for any religion that believed there was a moment that God created the universe.
As a matter of fact, Einstein rejected the theory because he believed it was too religious.
But, I am no expert on the subject and I will just let this be a disagreement.