The Abyss, where Daath resides, is the gulf or the chasm between the Noumenal (the Spirit) and the Phenomenal (everthing else which is not the Spirit). The Abyss exists between what is real and what is illusionary; between the ideal and the actual; the potential and the manifest.
Above The Abyss, all opposites are reconciled as there cannot be any duality above the Abyss. Below The Abyss all things are in duality.
The Abyss may be described as the gulf separating the individual soul from its source.
It is said that unresolved and irrational elements of the individual 'exist' within the Abyss - which cannot therefore truly be crossed without the elements being completely resolved. It is also said that to cross the Abyss, the Adept has to leave everything behind and give up all that he/she is.
In the Abyss the great demon known as Choronzon is met. It is the arch-demon of dispersion of the individual's false knowledge and is therefore sometimes known as the consumer of human consciousness.
Choronzon can reap major havoc in the life of an Adept it correct precautions are not in place or if the Adept permits the strong displines, gained through the journey up the tree, to not be in place.
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Source: The Complete Guide to the Kabbalah by Will Parfitt ISBN 0-7126-1418-4
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