From: http://www.rexresearch.com/bardon/bardon.htm

                        I

[Tone: G.. Color: Opal.. #: 10.. Element: Earth.. Organ: Left Kidney]

Akasa: In the akasa principle this letter oscillation is subject to fate, i.e., to the karma law, which is the law of cause and effect. All doings and all actions, all life, come under this letter oscillation. Likewise, the law of evolution of everything that has been created is expressed by it. At the same time, Divine Providence in His most subtle form is manifested in this letter oscillation. In the alphabet, letter “I” is the tenth letter and number 10 represents the one as its highest form in the akasa principle.

Mental: In the mental body, this letter oscillation is analogous to memory, remembrance and conscience. By the “I” oscillation, the rhythm of 10, the quabbalist is able to enliven everything as he pleases, and thus master it. At the same time, he achieves the spiritual ability to evoke any remembrance in his memory or the memory of someone else and, furthermore, to sharpen or weaken the conscience of a human being, i.e., the subtlest form of Divine Providence, depending, in each case, on what the quabbalist intends to achieve by the help of this letter oscillation. In short: all the faculties regarding memory and conscience in the mental plane may be comprehended and mastered by this letter oscillation.

Astral: In the astral kingdom, this letter oscillation corresponds to the astral matrix with all its functions. As you know, the astral matrix is the connecting link between the material body and the soul. i.e., the astral body: it is the so-called principle of life. It is also a known fact that the astral matrix, and with it the whole body, is kept alive by breathing. By the help of this letter oscillation, the quabbalist is also in a position to get under his perfect control the breath with all its aspects and ways of application. Likewise by this letter oscillation, he is able to make a body that is already dead breathe again by banishing the astral matrix back into the dead body and by reuniting body and soul. After this it will be easy for him to tie the desired spirit or mental body to the matter and to restore the human being to life again.

Material: In the material world, this letter oscillation corresponds to all laws of analogies between the micro-and the macrocosm. Everything that has shape, measure, number and weight. has been created by the help of this letter oscillation. If the quabbalist can master this letter oscillation, he will be able to evoke the greatest miracles in the material world by using the respective analogies to shape, measure, number and weight. As one can see, shape, measure, number and weight are the chief components of the material world, and by getting this letter oscillation under his control, the quabbalist becomes their absolute master. It stands to reason that he will also be able to become a perfect metaphysician, too and, furthermore, to comprehend all laws presently still unknown to our physical world and to apply them, as he pleases, in all fields.

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The quabbalist was taught, one after another, how to impregnate his mental, astral and physical bodies by means of single letters in order not only to take up certain oscillations within himself, but also to evoke these in different planes. Furthermore, he was taught by frequent repetitions and practical operations, to give a letter the dynamics– power of expansion necessary for his quabbalistic work; likewise, he attained the faculty of working inductively and deductively, i.e., of condensing and de-condensing, i.e., of bringing about effects in the mental matrix — astral kingdom and in the physical body —- the material world. In doing this, he has appropriated to himself not only the quantitative faculty of expansion of the mental, astral and the material body, but also the ability of giving the individual powers — quantities — their analogous qualities. Not until having learned this, did the letter uttered by the quabbalist become magic, i.e., dynamic and thus creatively effective.

Thereby he has enlivened the regions appertaining to the elements, strengthened the powers therein in analogy to the universal powers, thus bringing them into line with each other. His microcosm, i.e., the miniature world, has been brought into perfect harmony with the macrocosm and the quabbalist has taken full account of this legality in accordance with the Hermes plate which says “That which is above is also that which is below“.