"There is a type of magical work that enables a man to get control of his Etheric Body. So much so that he can do many strange and powerful things with the Etheric Body on the physical plane. It is possible during certain times of the 24 hour period of a day to “thicken” the Etheric Body so that it can be seen and felt by others. The Egyptians had developed this type of magic to a great degree. They had a very common symbol for this Etheric double or Ka as they called it. The symbol was two uplifted arms joined in the middle where the shoulders would be..." — Ophiel
Astral Bodies and the Phenomenon of Repercussion
During "ordinary" astral projection sessions, no physical danger exists and serious psychological dangers are quite uncommon, as the experience is more or less a form of controlled dream-state. Nonetheless, the phenomenon in which astral bodies sometimes become visible to other third-party observers has been observed since antiquity by many different cultures, and in many different contexts. In some cases accounts exist of such tangible astral doubles being capable of inflicting or sustaining physical injuries.
The theosophist Charles Leadbeater referred to the "strange and little-known phenomenon called repercussion, by means of which any injury done to, or any mark made upon, the materialized body in the course of its wanderings will be reproduced in the physical body." The ability for physical wounds to appear on a human body from no visible or objective physical source is is best known through the phenomenon of stigmata, but the same general effect has often been demonstrated by hypnotists who place subjects in a deep hypnotic state and suggest that the tip of a pencil or a piece of ice is a lit cigarette, after which they touch the subject's arm and cause a physical blister to appear. Deep hypnotic trance states are likewise necessary to induce projection and to sustain conscious travel in the astral dimensions.
Ancient Egypt and China
The Egyptians distinguished between the etheric body (ka) connected to the physical body and the astral body (ba) housed within the etheric. The latter was independently projectable under a variety of circumstances, while the etheric body usually remains closely attached to the physical until after death. However, as Ophiel suggested in the quotation above, various practitioners of astral travel throughout the ages have known of means by which the density of the astral matter can be "thickened."
Some schools of Taoist alchemy also made this distinction, and suggest that the astral body is an invisible or dreamlike projected body, while the more advanced projection of the etheric body results in a projected double that actually appears tangible and can even cause change to the physical world. One of the Eight Taoist immortals Han Xiangzi was fabled to be able to lie asleep snoring in one room and project his spiritual double into a banquet room where he greeted some officials. The officials investigated and found his sleeping body in the other room, after which his double walked back into the room and merged back, whereupon the sleeping body woke up again.
Ancient Germanic Lore
Ancient Germanic lore is rich with accounts of such projections. Odin could lie as if asleep and project his consciousness out of his body, and was said to be able to fight battles by possessing (or shape-shifting into) a huge bear— but any wounds sustained on the body of the beast would then appear on his own inert physical body.
Another account describes Seidr-women who entered a state of deep trance while their physical bodies lay inert on a raised platform (seiðhjallr). They projected out of their bodies travelled on the back of a monstrous whale to attack enemies on board a ship, to prevent them from reaching land. The company on board the ship fought back, however, and the death blows dealt to the projected doubles broke the physical backs of the witches, who toppled dead from the high platform.
In a non-combative context, the Chronicon Norvegiae related the story of a shaman who entered a deep trance to seek out the soul of a woman who had suddenly died. A dreadful wound suddenly appeared on the shaman's body during this work, killing him. Later another shaman managed to revive the woman, who said she had seen the spirit of the first shaman swimming in animal form when someone struck the beast with a weapon.
Witches & Werewolves
Later Germanic folklore passed down through the centuries is also filled with accounts of witches and werewolves whose projected astral bodies became visible to observers, as well as accounts of these projected astral doubles sustaining injuries which appeared on the physical bodies.
The C. E. Law of Vastgotaland records an account from the 1300s in which a witch travelling in spirit form became visible to an observer, who confronted her with the words: "Woman, I saw you riding on a fence switch with loose hair and belt, in the troll skin, at the time when day and night are equal."
There is a large tradition of animal shapeshifting in European lore. In many cases the shapeshifters involve battles between various clans or cults who project their astral doubles in animal form to do battle over the fate of the harvest. Sometimes these projected doubles would be seen visibly, as would those of astral travelling witches in flight.
Many German werewolf legends also speak of isolated practitioners of malicious magick, who could transform into werewolves or other sinister beasts by putting on an enchanted wolf-belt or strap. This was usually done to steal livestock, but some werewolf legends also involve robbery, murder, or vengeful motives. In many such legends a particular person would be suspected of menacing a village, wilderness area, or other locality, and when the werewolf was wounded the prime suspect would later be discovered bearing the same injury.
Religious Bilocation & "Ecstasies"
Religious ecstatics have a long history of entering deep trance states and having astral visions capable of generating physical wounds. Stigmata is the most well-known example of this phenomenon, in which the physical wounds said to have been inflicted on Christ during the crucifixion physically appear on the hands of devout religious believers. However, the repercussion phenomenon has taken place in many other contexts as well.
Claude Lecouteux collected a number of such accounts in his book Witches, Werewolves and Faeries: Shapeshifters and Astral Doubles in the Middle Ages. In one of these, Guibert of Nogent related the account of a woman who slept in a haunted cell in Trinity Monastery and had an astral vision of evil spirits in the infernal planes. A spark from the hellish fires struck her in the eye, ending the vision. As Guibert recounted: "It was confirmed that what she had seen in her dream, she had actually suffered physically; the real evidence of her wound came to confirm the authenticity of her vision." Similarly, in 1104 a monk at the monastery of Fly had an astral vision of a demon which struck him in the chest with a thrown rock. After this astral assault, "for forty days his suffering almost led him to the gates of death."
Lecouteux speculates that clerics may only have rarely noted accounts involving physical wounds since Christian doctrine required that visionary "ecstasies" be uniquely spiritual phenomena. However, he cited the Alexandrian theologian Origen's Ressurection, in which Origen states that souls are spiritual, but that immediately after death they take on another subtle body exactly like that which the spirit has departed — the astral body.
Astral Visions & Telepathic Hypnosis
The ability for certain individuals with an intense degree of astral sensory perception to manifest astral thought-forms visible to other individuals was illustrated by the devoutly religious Columba of Rieti, a young girl living in the late 15th century. Columba engaged in religious devotions of a decidedly shamanistic character, such as scourging herself multiple times every night to induce a profound state of hypnotic trance ("ecstasy"), during which she often had dramatic astral visions. One night Columba's priest saw a globe of fire floating over her house, and when he hurried over to investigate the vision, Columba told him she had seen the star of Bethlehem filling her chamber with light. The phenomenon was not explainable merely by the power of suggestion, since the priest was not aware that she was having "ecstasies" or what it was she was seeing in her astral vision, until he entered the house to investigate.
This phenomenon of shared visions has also frequently been associated with crowd madness and "mass hallucination," in which large groups of people see the same astral visions simultaneously. The phenomenon need not be negative, as illustrated by Columba's manifestation of the holy star, but was most likely caused by the same occulted principles enabling multiple individuals to witness the levitations of saints or the flights of the astral bodies of witches (which were often mistaken for the physical bodies of the witches in flight).
The "overlapping" of the astral and physical dimensions which exist in the same space simultaneously is a very likely explanation of these sort of accounts. The fact that human minds are connected on a subtle energetic level has now been brought into the new physics (as has the existence of multiple overlapping dimensions). A "concatenative aspect" by which minds are joined was one of the key axioms needed to make new findings in quantum physics explicable, along with the spatial and temporal extension of the mind, and its dominance over the material. The same principle has long been a mainstay of occultism, and is also a demonstrable phenomenon via telepathic hypnosis — the existence of which was proven in tightly controlled laboratory experiments in Leningrad by Leonid L. Vasiliev as early as the 1920s and 30s.
Astral Visions, "Hallucinations" and Thoughtforms
What is perceived in a shared astral vision may be a phantasm constructed by the imagination — which takes on a measure of reality on the astral plane due to the mind's shaping thought into energies — or it could be an actual astral entity with an independent existence of its own, as in the case of the projected doubles of witches or saints. When such visions have positive connotations for religious believers this is often considered a miracle, while similar phenomena which has negative connotations (or which they simply dislike) is declared to be the work of evil powers. Those who don't want to believe in the phenomenon in any context simply term such experiences "mass hallucinations" but are completely at a loss to explain the operative mechanisms enabling such shared hallucinations to occur.
An astral thoughtform of a non-enduring nature is a "hallucination" in the same sense as the "positive visual hallucinations" produced by stage hypnotists. Stage hypnotists open doorways to the subconscious minds of their subjects and then cause them to literally see objects, people or scenes that are not physically present in the physical plane, as well as completely altering their perception of reality in other respects. Such "hallucinations" are created by the subconscious mind in response to the hypnotist's commands, but are not entirely without tangible existence — they actually do exist (however fleetingly) in the astral dimensions as energetic "thought-forms" created by the subconscious minds of the individuals placed in the deep hypnotic trance state.
Whenever something is strongly visualized — even the pages of a book or images on a computer screen — it takes on a measure of energetic reality and becomes clearly visible on the astral dimension closely overlaying the physical, even if only for a brief period of time. Once one person sees such an astral construct and focuses intense concentration on it, it takes on a stronger measure of energetic reality in the astral dimension and can apparently be observed more easily than before by third parties. The ability to sustain concentration and focus energy on an astral thoughtform until it takes on an enduring reality is another traditional mainstay of magick and occultism, which are enabled by the art of hypnotism— the opening of doorways to the subconscious mind.