Ayin and Yesh

Ayin (Hebrew: אַיִן‎‎, meaning "nothingness", related to Ain-"not") is an important concept in Kabbalah and Hasidic philosophy. It is contrasted with the term Yesh ("something/existence/being/is"). According to kabbalistic teachings, before the universe was created there was only Ayin, and the first manifest Sephirah (Divine emanation), Chochmah (Wisdom), "comes into being out of Ayin." In this context, the sephirah Keter, the Divine will, is the intermediary between the Divine Infinity (Ein Sof) and Chochmah. Because Keter is a supreme revelation of the Ohr Ein Sof (Infinite Light), transcending the manifest sephirot, it is sometimes excluded from them.

Ayin is closely associated with the Ein Sof (Hebrew אין סוף), which is understood as the Deity prior to His self-manifestation in the creation of the spiritual and physical realms, single Infinite unity beyond any description or limitation. From the perspective of the emanated created realms, Creation takes place "Yesh me-Ayin" ("Something from Nothing"). From the Divine perspective, Creation takes place "Ayin me-Yesh" ("Nothing from Something"), as only God has absolute existence; Creation is dependent on the continuous flow of Divine lifeforce, without which it would revert to nothingness. Since the 13th century, Ayin has been one of the most important words used in kabbalistic texts. The symbolism associated with the word Ayin was greatly emphasized by Moses de León (c. 1250 – 1305), a Spanish rabbi and kabbalist, through the Zohar, the foundational work of Kabbalah. In Hasidism Ayin relates to the internal psychological experience of Deveikut ("cleaving" to God amidst physicality), and the contemplative perception of paradoxical Yesh-Ayin Divine Panentheism, "There is no place empty of Him".

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