The fusion of זעיר אנפין and מלכות is called ייחוד זון — the unification of זעיר אנפין and נוקבא (מלכות).
This represents the union of the six sefirot (considered "masculine") with the seventh, מלכות ("feminine").
The mission of man in this universe of the Divine concealment is to make His presence evident, by living according to His commandments and utilizing the physical world for Divine purpose. Each of the names applied to G-d describes a particular aspect of G-d. One name, הויה, describes His transcendence—G-d before Whom all creation is naught. Another name, אלוקים, indicates power, the creative and sustaining force—G-d Whose hand may be detected in His works.
The theme of יחוד (yichud, unity), recurrent in Kabbalah and Chasidus, is the union of both aspects—that transcendence become immanent, and that creation cease to conceal G-d. This unity is brought about on different planes, depending on the act which produces that union. Self-sacrifice causes one sort of union; Torah study and mitzvah observance causes another. The union called זו"ן (noted in our text) is of the latter order.
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