My wife and I recently explored a subterranean cavern in Pennsylvania. Those who go caving can attest to the fact that caverns are a strange realm. According to cognitive scientist, Philip Lieberman, burial might be one of the earliest forms of religious practice. Ancient people began to associate the afterlife with a dark underworld. It was assumed that the dead must reawaken in a subterranean realm.
We got to see stalagmites that resembled chthonic creatures. Stalagmites are deposits of calcium carbonate formed from calcareous water. It is a sort of natural alchemy that can require thousands of years. One stalagmite resembled a horned devil. It was easy to imagine the ancient Greeks transforming stalagmites into characters that might populate their gloomy underworld. It was the pareidolia in all its glory.
The subterranean river that flowed through the cavern reminded me of Styx. The faint odor of sulphur reminded me of hellish brimstone, as well as the alchemical sulphur that adheres to the genitals and coagulates the alchemical mercury into the sacred sexual fluids.
In Cabala, the underworld is associated with the path of Tav that connects Malkuth and Yesod. Suspended between the Earth and the Moon the underworld is a sublunar realm where illusions and phantoms hold dominion. It is the cave of Plato where the shadows of ignorance hold sway.
It is at the threshold between Malkuth and Yesod that one first encounters the entity known as the ‘Dweller of the Threshold.’ This spectral entity resides between the physical and spiritual planes. It often takes the form of a phantom clad in a black hooded cloak.
The concept of the ‘Dweller of the Threshold’ had its beginning in the writings of Edward Bulwer-Lytton, an English writer and politician. In his book Zanoni, this phantom seeks to prevent unprepared candidates from pursuing higher spiritual aspirations.
According to Blavatsky, these entities are the “maleficent astral doubles of defunct persons.” She goes on to suggest that the ‘Dweller of the Threshold’ is the astral shell of a person’s previous incarnation drawn to their new incarnation via magnetic attraction.
The ‘Dweller of the Threshold’ stands at the threshold of the astral plane where it seeks to frighten us from pursuing our Great Work. It embodies the fear and angst that holds us back from spiritual attainment.
The ‘Dweller of the Threshold’ is also the guardian of the mysteries. It protects the Western esoteric tradition from being misused for evil. Through causing the unworthy to abandon their quest it keeps the mysteries out of the hands of those who might have abused them.
“Fear is failure.” The neophyte must face his fears and leave them behind before he can proceed any further on his spiritual path. “Fear is death.” Fear can kill any spiritual quest dead in its tracks.
The way past the ‘Dweller of the Threshold’ involves allowing oneself to be guided by the light of their conscience. Additionally, the teachings of a mentor or lodge can act as an intermediary guiding principle that can assist people with navigating through their fears.
But let us not forget that the underworld is also a place of light. “And the light shineth in darkness; and the darkness comprehended it not.” The light dwells in the darkness. There was light to be found in the subterranean temples of Mithras. The tomb of CRC was illuminated with the light of the divine. “Visit the interior of the earth, and by rectifying what you find there, you will discover the hidden stone.” Once the light in the underworld is rectified the lapis philosophorum can be found.
 Philip Lieberman. (1991). Uniquely Human. Cambridge, Mass.: Harvard University Press. p. 162. ISBN.
 Helena Petrovna Blavatsky, The Theosophical Glossary (Krotona, CA: Theosophical Publishing House, 1973), 106.
 Helena Petrovna Blavatsky, Collected Writings vol. XII (Wheaton, IL: Theosophical Publishing House, 1982), 636.