Cabala is a system of knowledge with its roots in another age, a previous stage of human development, when people experienced the world very differently than we do now.
According to traditional stories, Adam was given a book containing the complete future history of the world, with all the secrets and mysteries of human existence laid bare. The mystical teachings of that primeval book have filtered down through the generations, contributing parables, metaphors, and allegorical stories to Cabala's body of tradition and knowledge.
From a historical point of view, a significant amount of material found in the Old Testament, the prime source of cabalistic learning, is now known to have been written down in the ancient Syrian kingdom of Ebla, as early as 4500 years ago; contemporary with the construction of the great pyramids in Egypt. From Ebla and ancient Mesopotamia, these traditional stories stretch back to the stone age. Old Testament themes such as Jacob's Ladder, Ezekiel's Field of Dry Bones, and Abraham's Covenant, have been commonly found in slightly varied forms, among diverse and widely-isolated shamanic traditions.
Whether these traditional stories derive from the Book of Adam, or from some kind of archetypal patterns in a collective unconscious, they plainly convey a numinous, pre-rational, perspective. Conversely, philosophers like McLuhan and Leonard Shlain explain in detail how our modern information technology is Rationalist. It's linear and denotative; and often, a fortiori, even digital as well.
We generally view the world as Cartesian, regardless of the fact that Bell's Theorem, Heisenberg's Uncertainty Principle, and other established principles of quantum physics, tell us that the universe, in a most basic way, does not operate in the linear manner Descartes imagined.
We primarily understand and transmit ideas by transcribing them sequentially, point-by-point, cause-then-effect, step-by-linear-step. With the teachings of Cabala, the method is totally different. Here, as in psychologist Eric Fromm's Forgotten Language, the target ideas are not approached directly or linearly, but are rather woven wholesale, between the lines. It's a completely different way of handling information.
The word "cabala" means to receive. Traditionally there are four levels of receiving information from cabalistic teachings – or anything else for that matter. "Pshat" is the first and lowest level understanding, and is likened to the cabalistic world of Assiah (the physical/material realm), and the element Earth. Ideas and meanings in Pshat are as simple and tangible as dirt. There are no symbols, metaphors, or allegories on this level of understanding; each word in the story has only its literal denotation. Anyone who can follow the language and the train of events in a story receives understanding on the level of Pshat. In Pshat, the Garden of Eden story is about two people who get in trouble for eating an apple they were told not to eat. A rich man / poor man story, on the level of Pshat, is about one man with money, and another man without; and Samson and the Lion is about a man defeating a large feline.
On the three higher levels of understanding, a myriad of connotations arise. Here, a rich man / poor man story can be an allegory about a person and their God, or their intuition; or it can represent a soul/body duality, etc. Samson and the Lion becomes archetypal; now he might be the enlightened hero overcoming the beast on the eighth trump of the Tarot - higher consciousness overcoming its lower, animal nature. It can be a metaphorical story about Superego overcoming the beastly Id, or other such things.
Cabala's second level of understanding is called "Remez", and is likened to the cabalistic world of Yetzirah (the sentient/emotional realm), and the element Water. Remez is the level of deductive reasoning. Meanings which can be deduced from elements contained in a story, but which aren't actually stated per se, belong to this level of receiving. Remez presents more than a simple story line, and can often lead one to a moral or lesson. A person who hears the Garden of Eden story, on the level of Remez, could be left, among other things, with a message such as: don't disobey the authorities, or you might lose their shelter and protection.
Cabala's third level of understanding is called "Drosh", and is likened to the cabalistic world of Briah (the cognitive/intellectual realm), and the element Air. This is the level of inductive logic. Meanings on the level of Drosh are dependent on context, and can be as shifting and nuanced as a gusty breeze. A single meme, idea, or figure, without a context or ground to give it reference, has little substance in Drosh.
It has been said that Drosh will yield understanding only to one who brings their own question or frame of reference. For example, a man with a troubling Oedipus Complex might bring that frame of reference to the Abraham-Isaac story. His understanding of that story will be much richer, on the level of Drosh, than that of a person who is unconcerned with issues of paternal authority.
It's on the level of Drosh that Jung's archetypal themes find their resonance in personal context, and seem to strike such deep chords of personal meaning. And it's on this level that a person can get the feeling that a story or drama was somehow written personally for them, and for their personal situation.
The top level of understanding is called "Sod", and is likened to the cabalistic world of Atziluth (the holistic/spiritual realm) and the element Fire. As Fire is the transcendental member of the classical four elements, so Sod is the transcendental level of receiving and understanding. This inner understanding transcends the capabilities and applications of logic, analytical forms, and verbal languages. The understanding of Sod is holistic, integral and gestalt. It has been said that on the level of Sod the lover and the beloved, the knower and the known object, the figure and the ground, are one with each other. This kind of integral understanding can be experienced, but it's introspective, and can not be described in a science book, or directly communicated to any external being.