Perhaps 'proved' is too strong a word for it, KBS. But I think we have raised a pretty big question mark in various discussions all over this board. Yet it's all quite fragmented, and so perhaps it might be a good idea to attempt some kind of pull together conclusion of where we're at with it, thus far.
For me, what's interesting is not to try and prove that Jesus didn't exist, or God doesn't exist, although I do tend to get involved in those kind of discussions. But what I've been doing the past 10 years, through my research, is tracing a line, a development of an idea, from the ancient shamanic way of life, once practised all over the world, through the Mystery schools and on into religion. In doing this, I can see how one idea led to another, led to another, led to another, and how the political landscape at each juncture fed into and informed the prevailing collective view about who God was.
There is enough evidence in mythology to show that, if you go back far enough, people lived in a symbiotic partnership with the spirits, each person having their own connection with their own guiding spirits as well as the spirits of nature. After some time - we don't know how long but probably with the advent of agriculture and, thus, each person developing their own skills - this gift of communication became more specialised into one or two people in each tribe and, in Siberia at least, these people were known as shamans.
The earliest records we have of shamanic practice are the Indian Vedas, and also some of the Sumerian literature that was inscribed on tablets in cuneiform letters, such as the Epic of Gilgamesh and the Descent of Ishtar. We can date these works to around 3,000 BC.
After that, the next layer of sacred literature - the Vedanta, the Buddhist sutras, the Tao etc - seems to be another step away from each person having their own relationship with the sacred. The spirits become more god-like, more remote, and a new way of relating to gods/God came into being. No longer was the shaman asked to go into the causal dimensions to sort out any problems experienced by the tribe. Now, the doctrine of karma (or what the Christians call 'original sin') came into being. So then the only way to a happier life was to pay back what you owed by good works in the hope of a better afterlife or next life, depending on whether your religion included reincarnation in its doctrine.
A thousand years or so later came the Mystery religions, where adepts were taken in and sworn to secrecy through complex initiations and then revealed the 'divine secrets'. This was across Mesopotamia, Middle East, Egypt, Greece and Rome. For the main part, the connection with the spirits was totally lost by now, and so the secrets consisted of the by-products of that former relationship with them, such as astrology and mathematics, and an awful lot of superstitious claptrap thrown in besides. By now the 'gods' (who remember, were originally our partners) had been petrified into statues on plinths and were the objects of worship of us 'lesser beings' who could "never even dream of reaching such heights of divinity -- but don't forget the collection bowl on your way out!"
This gradually morphed into religions, who in the main, took the myths and stories of the shamanic and the mystery rites, and made them into their own for, most probably, political purposes. For instance, Yahweh was originally a god in the Canaanite pantheon. He had some sort of small role, but the real hero was Ba'al and the king was El. The Hebrews, being originally Canaanites, had these stories in their blood, in their race memory, and so for reasons which we've been discussing but cannot really prove, took Yahweh out of this pantheon and promoted him to the supreme Godhead. In Exodus, Moses tells the Children of Israel that their God, who used to be known as El, should now be called Yahweh. Elijah also supports this move by calling for the deaths of the priests of Ba'al, the hero of the Canaanite pantheon.
Along those lines, there is also a Canaanite Dani'il who was rewarded by the king for his dreaming prophecies. This story dates at least a thousand years earlier than Daniel in the Bible.
So it's easy to see now why the 'Children of Israel' kept falling back into being polytheists - it was who they really were.
Anyway, this is a bit of a 'history of the world in five minutes' and I've missed out loads, and probably generalised too much, but it's just to show the progression. (And I haven't even mentioned Zoroastrianism as its date of origin is too contentious - my own view, though, is that it's almost entirely derived from the Vedas, or at least an earlier mythology that was common to both the Indians and the Persians.)
But this progression shows that religions are the result of a common, worldwide collective consciousness that developed over thousands of years more or less simultaneously in every country, in every civilisation - well, certainly in Mesopotamia and the Middle East, anyway, where the wandering story tellers and traders were the carriers and planters of the seeds of these stories.
So this is why I said to you that you might want to look at how the serpent is regarded in other myths. This is because, for so long, the history of Israel has been treated in isolation from other similar civilisations in the area - because of the treading on eggshells around religious sensibilities. But that time has passed, and the archaeology and sacred literature of the Hebrews is now being treated in a much more egalatarian way. It is now being studied in context with the whole geographical area, and from that, with their roots revealed, the Biblical stories take on a whole new light. The Garden of Eden story, thought to be the oldest in the Bible, can now be seen in context with other civilisation's stories that are centred round what is loosely labelled as 'The Fall'.
To conclude, my view is that by studying in this way, by coming out of the silo thinking promulgated by the Church over thousands of years, one can better appreciate the stories in the Bible, which are mainly written in metaphor as myths always are, and thus enhance and deepen one's spirituality, one's relationships with the guiding spirits and the spirits of Nature - who, by the way, are dying to get down from their plinths!
As you can see, I'm not an atheist!