We’ll start with the Mishnayot of this section:
הספירות הם הארות שניתנו ליראות, מה שלא ניתן אור הפשוט א”ס ב”ה:
Sephirot are those illuminations that were allowed to be envisioned (prophetically), unlike God’s own simple light (and other lights that are more sublime than the Sephirot under discussion, which cannot be envisioned whatsoever).
כל ספירה היא מדה אחת מן המדות של א”ס ב”ה, אשר ברא בם את העולמות, ומנהג אותם. שברצותו שתהיינה נודעות, עשה שכל מדה תראה בסוד הארה אחת, שבראות אותה – מבינים המדה ההיא. ובראות תנועות ההארה ההיא – מבינים מה שנעשה בהנהגה במדה ההיא בזמן ההוא:
Each Sephira is an attribute of The Infinite that He used to create the (various esoteric and concrete) worlds and which He (now) uses to govern them.
Now, since He wanted them to be known of, He had each attribute appear as a single, mystical “illumination”. So by “envisioning” it we can understand the attribute itself, and by “envisioning” its movements we can understand what would be taking place in the governing process through that attribute at that time.
And we’ll add these essential points:
The Sefer Yetzirah is the first printed work to speak of the Sephirot. It speaks of “ten Sephirot of ‘sheer nothingness’” referring to their utterly immaterial nature or, put another way, to “ten ineffable Sephirot” (1:2) .
 The Sefer Yetzirah also speaks of close homonyms to Sephirot, “Sepher (book), S’phar (number), and Sippur (communication)” (1:1) which tell us something about their overall makeup.
For as Rabbi Aryeh Kaplan put it, “Like a book, each Sephira can record information. The Sephirot thus serve as a memory bank in the domain of the Divine. A permanent record of everything that has ever taken place in all of creation is thus made on the Sephirot…. The Sephirot (also) introduce an element of number and plurality into existence. The Creator, the Infinite Being, is the most absolute unity, and the concept of number does not apply to Him in any manner whatever…. It is only with the creation of the Sephirot that the concept of number comes into being. In this mode, ever event and action is measured and weighed by the Sephirot, and the appropriate response is conceived and calculated…. The Sephirot are (also) the means through which God communicates with His creation. They are also the means through which man communicates with God. If not for the Sephirot, God, the Infinite Being, would be absolutely unknowable and unreachable” (Sefer Yetzirah, Aryeh Kaplan, p. 21).
(c) 2010 Rabbi Yaakov Feldman
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