"In considering the causal body (this "Temple of the Soul"), we are dealing specifically with the vehicle of manifestation of a solar Angel who is its informing life and who is in process of constructing it, of perfecting it, and of enlarging it, and thus reflecting on a tiny scale the work of the Logos on His own plane." (A Treatise on Cosmic Fire, p. 1110)
"The causal body is a collection of permanent atoms, three in all, enclosed in an envelope of mental essence . . .
Therefore, you have at the moment of individualisation, which is the term used to express this hour of contact, on the third subplane of the mental plane, a point of light, enclosing three atoms, and itself enclosed in a sheath of mental matter. The work then to be done consists of:
1. Causing that point of light to become a flame, by steadily fanning the spark and feeding the fire.
2. Causing the causal body to grow and expand, from being a colourless ovoid, holding the Ego like a yolk within the egg-shell, to a thing of rare beauty, containing within itself all the colour of the rainbow. This is an occult fact. The causal body will palpitate in due course of time, with an inner radiation, and an inner glowing flame that will gradually work its way from the centre to the periphery. It will then pierce through that periphery, using the body (that product of millennia of lives of pain and endeavour), as fuel for its flames. It will burn all up, it will mount toward the Triad, and (becoming one with that Triad) will be re-absorbed into the spiritual consciousness, -- will carry with it -- using heat as the symbol -- an intensity of heat or quality of colour or vibration, that before were lacking.
Therefore, the work of the Personality -- for we have to view all from that angle until egoic vision may be ours, -- is first to beautify, build and expand the causal body; secondly, to withdraw within it the life of the Personality, sucking the good out of the personal life, and storing it in the body of the Ego. We might term this the Divine Vampirism, for always evil is but the other side of good. Then, having accomplished this, comes the application of the flame to the causal body itself, and the joyous standing by whilst the work of destruction goes on, and the Flame -- the live inner man, and the spirit of divine life -- is set free, and mounts to its source." (Letters on Occult Meditation, p. 30/1)
"The content of the causal body, is the accumulation by slow and gradual process, of the good in each life. The building proceeds slowly at first, but towards the end of incarnation -- on the Probationary Path and on the Path of Initiation -- the work proceeds rapidly. The structure has been reared, and each stone quarried in the personal life. On the Path, in each of its two divisions, the work of completing and beautifying the Temple proceeds with greater rapidity . . ." (Letters on Occult Meditation, p. 32)
"At a later stage upon the Path of Initiation, the causal body also disappears, and the initiate stands free in the three worlds. The astral body and the causal or soul body are -- in the language of esotericism -- supplementary to reality. They have a had a temporary reality during the evolutionary process, but (having served their purpose, and having endowed man with certain required assets -- consciousness, feeling, sensitivity, and ability to establish and register contact) they pass away, and the initiate remains, possessed of power over form, and a fully awakened consciousness. He is a soul, and the fusion is complete." (The Rays and the Initiations, p. 162)