Astral Light
The French occultist Eliphas Levi (February 8, 1810 - May 31, 1875) used the term "astral light" to refer to the medium of all light, energy and movement, much in accordance with the theory of the luminiferous ether commonly held in the nineteenth century. In his view the astral light was a fluidic life force that fills all space and living beings.
Years later, H. P. Blavatsky adopted the term and applied it in her writings. In The Theosophical Glossary, she defines it as follows:
Astral Light (Occult). The invisible region that surrounds our globe, as it does every other, and corresponding as the second Principle of Kosmos (the third being Life, of which it is the vehicle) to the Linga Sharira or the Astral Double in man. A subtle Essence visible only to a clairvoyant eye, and the lowest but one (viz., the earth), of the Seven Akâsic or Kosmic Principles. Eliphas Levi calls it the great Serpent and the Dragon from which radiates on Humanity every evil influence. This is so; but why not add that the Astral Light gives out nothing but what it has received; that it is the great terrestrial crucible, in which the vile emanations of the earth (moral and physical) upon which the Astral Light is fed, are all converted into their subtlest essence, and radiated back intensified, thus becoming epidemics--moral, psychic and physical.[1]
In Isis Unveiled she adds:
The same as the sidereal light of Paracelsus and other Hermetic philosophers. Physically, it is the ether of modern science. Metaphysically, and in its spiritual, or occult sense, ether is a great deal more than is often imagined. In occult physics, and alchemy, it is well demonstrated to enclose within its shoreless waves not only Mr. Tyndall’s “promise and potency of every quality of life,” but also the realization of the potency of every quality of spirit. Alchemists and Hermetists believe that their astral, or sidereal ether, besides the above properties of sulphur, and white and red magnesia, or magnes, is the anima mundi, the workshop of Nature and of all the cosmos, spiritually, as well as physically. The “grand magisterium” asserts itself in the phenomenon of mesmerism, in the “levitation” of human and inert objects; and may be called the ether from its spiritual aspect.[2]
Notes
Additional resources
Theosopedia, s.v."Astral Light," by Vicente R. Hao Chin, Jr., accessed February 6, 2011, http://theosophy.ph/encyclo/index.php?title=Astral_Light.