(1.) was a volcano. See the book, "Volcano", part of the "Planet Earth" Time-Life book series, Chapter 1 "The Awakening of the Dragon", page 36-37, describing a spire of molten lava that was extruded from the crater of Mt. Pelee after destroying the city of St. Pierre on the island of Martinique in 1902: "The spine, soon called the Tower of Pelee, was 350 to 500 feet thick at its base and varicolored, ranging in hue from ruddy brown to purplish, gray and white. At night, the spine glowed with a tracery of red incandescent lines, and frequently a luminous spot coud be seen at its tip"... This would have given off smoke/steam by day, and glowed "like a pillar of fire" at night.
Along with that, check the bible verses that describe Moses going up on the mountain to receive the ten commandments and see if you can guess what sort of a mountain it was.... I spotted that when I was a little rockhound who had just become interested in vulcanology; only 8 or 9 years old, and knew from that point on that the bible itself was simply the words of men...
The landscapes of Israel/Syria are pocked with Holocene volcanoes - eruptions which are 10,000 years old or younger. The primitive, superstitious, ignorant, nomadic Middle Eastern men who wrote the bible would have looked upon the fire of a volcanic eruption as something magical from their god... Which also may tie in with a theory I read about some years ago that I haven't had time to check on - yet. Something about an archaeological theory that YHWH/Jah/whatever was originally an offshoot of the god Ba'al - Ba'al being a god of lightening and also possibly a god of fire. I have to look into that again....
(2.) is a naturally occuring phenomenon in some areas of the Middle East. There was some discussion (don't have time to find the websites now but will post them later if anyone's interested) about the site of the sea being mis-translated as the "Red" Sea but should have been translated as the "Reed" sea - much shallower. The website or sites discussed the probability that the "Reed" sea was shallow enough for a strong east wind to temporarily dry up a passageway sufficient for a widely-spread-out tribal group to pass through, but a heavily-armed military troop (or troops - especially with heavily armored chariots) would tend to break through a lightly dried-up surface crust and bog down in the sodden soil that was only lightly dried out.
(3.) The term "Christ" originally applied to the so-called "Pagan" Greek God Dionysus, who coincidentally was born of a virgin (or is that Mithras??) in a humble cave (which is the original translation of the term nowadays translated as 'manger'), was humiliated at the hands of his enemies, cruelly executed only to be reborn and triumphantly dominate them. His sacrificial death was symbolized by the cutting down of the dead grapevines, and after the autumnal harvest when the grapes had been harvested and turned into wine, a ceremony in which the wine was drunk was said to be the symbolic drinking of the sacrificial God's blood, which he shed for the benefit of mankind.... Sound familiar??? The worship of Dionysus began at least ONE THOUSAND TWO HUNDRED years BEFORE Jesus was a gleam in a Greco-Romanized Jewish scribe's eye.... So who plagiarized from whom, eh??
(4.) The snake was a sacred symbol long before this story came along. It was often associated with Goddess worship, which may have been the reason that both the woman and the snake were 'demonized' in this particular story. By the way, it is highly probable that the book of Exodus is actually much older than the book of Genesis, despite their respective positions in the bible, because in the book of Exodus Moses made a copper/bronze image of a snake (on a stake) for the Israelites to look upon to cure them of their sicknesses. But in the book of Genesis, suddenly the snake is a symbol of evil. When I first ran into that story in Exodus, I read ahead several chapters in Exodus to see where the Israelites were punished for worshipping a graven image!! Imagine my surprise to find that, not only were they not punished, but this very example of hypocritical idolatry worship was a forerunner for the image of Jesus himself! That was another incident which proved the human origins of the bible to me - I was only 7 or 8 when I noticed that discrepancy!!
And there is so much more that I don't have time to go into right now...