In Christianity, the mystery of coming to consciousness is represented as the expulsion of Adam and Eve from the garden. Jung described the serpent as a symbol of nature's transformation in a twilight half-human which gradually came into opposition to itself. It didn't happen suddenly.
Myths contain an ambiguous wealth of unconscious information which can't be explained discursively. The psyche is a diffuse organ of perception whose wider perspective is supplemented by the focus and detail of consciousness. Beyond rational science lies an irrational pre-history of sensory, emotional, and intuitive functions that point back to a remote past -- but, also to the future: the psyche is is a mysterious continuum in which past, present, and future co-exist outside our conscious conception of time.
In its most urgent sense, the function of life is adaption to immediate reality, though the value of memory-images confirms that an orientation to the past is indispensable for it. But, time-awareness implies possibilities as well. As myths also portend collective tendencies, dreams sketch out possibilities for individual development; it's how the unconscious deity of wholeness reflects our fate -- pardon the subjectivity.
Jung demonstrated how the snake symbolizes instinctual wisdom: the winding by-paths of earth-bound existence, the frightening hidden nature of an animal reality which strikes suddenly from unseen places, the forked tongue of a dual nature which deceives as it yet speaks the truth. As we evolved, so did the image -- into a part-human figure as did older animal deities which described the dawn of humanity.
Over the many centuries of evolution depicted in the Old Testament, the serpent reappeared as Satan, much as the Sphinx symbolized the humanization process in Egyptian mythology. It seems crazy to me today that as a youth I was instructed to believe literally in such a mythical figure as had the tail, horns, and hooves of an animal yet to realize its full human potential; though, I see it in myself and the world, still.
For many, it's difficult to identify anything real in it. To the rationalist and the atheist, it's merely silly. To the politician and the preacher, it's more a tool for manipulation. But, even the true believer is coming to doubt its significance in an age of literal material truth. A major shift in consciousness finds it mostly in the museum of outdated fantasy -- diffused back into the unconscious -- waiting to be re-defined. But, historical analogy is essential for a sense of the symbolic blueprint of unconscious functioning.
In the biblical context, snake and devil condense into one idea the opposition required to accept or reject; to choose amid a world of possibilities in a human prototype slowly awakening from a dreaming instinctual awareness. Expulsion from the garden signified that fateful split from unconscious nature, its secret relations eloquently and poetically portrayed as the drama between god and man.
The last collective image describing the dark side of our natures is that figure of the Devil. Whose mind doesn't respond to the leering mythical half-beast's evil grin, the long arrow-headed cat's tail, the beastly horns, the cloven hooves? These attributes demand to be reassembled in a new way to form any meaning in the strange guise they present. He's now the scattered and undefined anxiety of fear, chaos, confusion, and projected hostility in the new dawn of an uncertain technological future.
The horns of this fading fantasy figure equate with the forked tongue, and both point to a dual nature: the fork in the head, a form of awareness, though a primitive one; the tongue, an ancient reminder of an opposed consciousness which would question even a god (a property the snake possessed, too, in the ancient trinity of animal, man and deity) -- and at the same time, the earthly opposite of the Word of humanity's highest aspirations.
Someone once told me of a dream he had of this very picture of the devil, its tail twitching like a cat's tail as it grinned eerily in its sphinx-like repose. It's this cat-like, feminine quality of repressed emotion which the unconscious seized upon to inform him of his dissociation. The arrow-head on the tail was the piercing depth his unconscious nature intended to point out his rational misconceptions of himself.
The Devil's unconsciousness is symboled by his dark nature, though his defining color is red. Erich Neumann described redness as instinctual excitation; and the sensuality of material desire now bids our loftiest scientific minds to uncover all its depth -- in concrete form. The beast would become human -- but it needs the assistance of other psychic functions. Goethe expressed something of the sort in the witch's kitchen when Faust was in need of a magic potion to make him fall in love: "It's true the Devil taught her how to do it. And yet the Devil cannot brew it."
His hooves describe the instinctual foundations of herd-like collective instincts which can easily overpower the freedom of the individual. Jehovah's commands, however, forbade the eating of herd animals with split hooves, reinforcing the idea of dissociation, but also the need for union which the myth of the garden decreed was the central theme of an individual spiritual life.
These ideas lie in the images as symbolic pointers to our division and the need for a spiritual reconciliation. The depth psychology which unearthed this new way of looking at our histories has only recently been established. The science of it is not yet recognized.