"In that Light shall we see light" paraphrase..

Each of us is recognized by the brilliance of his light. This is an occult fact. The finer the grade of matter built into our bodies, the more brilliantly will shine forth the indwelling light. Light is vibration, and through the measurement of vibration is fixed the grading of the scholars. Hence nothing can prevent a man's progress forward if he but attends to the purification of his vehicles. The light within will shine forth with ever greater clarity, as the refining process goes on, until - when atomic matter predominates - great will be the glory of that inner man. We are all graded, therefore, if it may be, so expressed, according to the magnitude of the light, according to the rate of vibration, according to the purity of the tone and the clarity of the colour.

- Initiation, Human and Solar

Through his meditation, discipline and service, man fans into radiant light, illuminating the three worlds, that point of light which flickered into being at the time of his individualisation in past ages.
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Humanity is the planetary light bearer, transmitting the light of knowledge, of wisdom, and of understanding, and this in the esoteric sense.

- A Treatise on White Magic

"In that Light shall we see light". A simple paraphrase of apparently abstract and symbolic words, could be given as follows: When the disciple has found that lighted centre within himself, and can walk in its radiating light, he is then in a position (or in a state of consciousness, if you prefer), wherein he becomes aware of the light within all forms and atoms. The inner world of reality stands visible to him as light-substance (a different thing to the Reality, revealed by the intuition). He can then become an efficient co-operator with the Plan, because the world of psychic meaning becomes real to him, and he knows what should be done to dispel glamour. It might be stated, that this process of bringing light into dark places falls naturally into three stages:

1. The stage wherein the beginner and the aspirant endeavour to eradicate glamour out of their own life, by the use of the light of the mind. The light of knowledge is a major dispelling agent in the earlier phases of the task, and effectively eliminates the various glamours which veil the truth from the aspirant.

2. The stage wherein the aspirant and disciple work with the light of the soul. This is the light of wisdom, which is the interpreted result of long experience, and this streams forth, blending with the light of knowledge.

3. The stage wherein the disciple and the initiate work with the light of the intuition. It is through the blended medium of the light of knowledge (personality light), and the light of wisdom (soul light), that the Light is seen, known, and appropriated. This light puts out the lesser lights through the pure radiance of its power.

You have, therefore, the light of knowledge, the light of wisdom, and the light of the intuition, and these are three definite stages or aspects of the One Light. They correspond to the physical Sun, the heart of the Sun, and the Central Spiritual Sun. In this last sentence you have the clue and the key to the relation of man to the Logos.
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The fact of the soul will eventually be proved through the study of light and of radiation, and through a coming evolution in particles of light. Through this imminent development, we shall find ourselves seeing more and penetrating deeper into that which we see today . . . The quality of the light which promotes and nurtures growth, vitality and fertility in the kingdoms of nature, has changed several times during the ages, and as it has changed, it has produced corresponding mutations in the phenomenal world.
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An intensification of the light is going on all the time, and this increase in intensity began on the earth at about the time when man discovered the [Page 241] uses of electricity, which discovery was a direct result of this intensification. The electrification of the planet through the widespread use of electricity, is one of the things which is inaugurating the new age, and which will aid in bringing about the revelation of the presence of the soul. Before long this intensification will become so great, that it will materially assist in the rending of the veil which separates the astral plane from the physical plane; the dividing etheric web will shortly be dissipated, and this will permit a more rapid inflow of the third aspect of light. The light from the astral plane (a starry radiance), and the light of the planet itself, will be more closely blended, and the result upon humanity, and upon the three other kingdoms in nature, cannot be over-emphasised. It will, for one thing, profoundly affect the human eye, and make the present sporadic etheric vision a universal asset. It will bring within the radius of our range of contact the infra-red and ultra-violet gamut of colours and we shall see what at present is hidden. All this will tend to destroy the platform upon which the materialists stand, and to pave the way, first, for the admission of the soul as a sound hypothesis, and secondly, for the demonstration of its existence. We only need more light, in the esoteric sense, in order to see the soul, and that light will shortly be available, and we shall understand the meaning of the words, "And in Thy light shall we see light".

This intensification of the light will continue until A.D. 2025, when there will come a cycle of relative stability and of steady shining, without much augmentation.

- Esoteric Psychology I