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It is a familiar saying that a well matched couple 'grow together', so as to come to a close resemblance in features as well as in mind. But do you know that between adept and chela - master and pupil - there gradually forms a closer tie; for the psychic interchange is regulated scientifically, whereas between husband and wife unaided nature is left to herself. As the water in a full tank runs into and empty one which it is connected with; and as the common level will be sooner or later reached according to the capacity of the feedpipe, so does the knowledge of the adept flow to the chela; and the chela attains the adept level according to his receptive capacities. At the same time the chela being an individual, a separate evolution, unconsciously imparts to the master the quality of his accumulated mentality.

Letters from the Masters of Wisdom, first series, p. 92, letter 43
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