Yichud means unification and comes from the root word יחד unified or one. A Yichud is a type of a kavana- special Kabbalistic intention.
Man's role consists in the restoration of the original harmony that was destroyed with the breaking of the Vessels; the unification of the name of G-d.
In other words, according to Kabbalah, our role is to achieve the “Tikun Olam”, rectifying the world through the spiritual intention of binding the spiritual and the physical realities as one.
The Arizal says that our role is to restore the connection between the two facets of G-d the Yud+Hey/ Vav +Hey, the intellectual and emotional parts of G-d’s names thereby uniting the above nature and nature realms.
This reuniting process are known as Yechidim, "Unifications". A great many yechidim were taught. All involve the meditative contemplation of the letters of the various names of G-d.
Israel, Torah and G‑d are bound together in a complete unity, as the Zohar states elsewhere, “the Holy One, blessed be He are, the Torah and Israel are all one,” and their unification is by way of the revealed and hidden aspects of each of them. This is an innate relationship, not one forged by any particular activity or event.
The most famous yichud is the “Shema- Hear Oh Israel, G-d is our Elokim, G-d is One”. The two names of G-d- YKVK and Elokim are joined and are one, creating the Yichud of the name YKVK and ADNI. The numerology of of both (26 and 65 respectively) equals 91 which also has the numerology of Amen.
On a basic level, Amen means true, on a deeper level, Amen means to unite. That is why after each blessing (beracha) an Amen is supposed to expressed. The two facets of G-d, the above nature (YKVK) and the within nature (ADNI) are united.
The numerical equivalents of the three letters of the last word of the Shema- Echad (One) Alef, Chet and Dalet – 1,8,4- are considered to comprise a basic kavanah: visualize drawing down God who is One -alef, through the seven heavens and earth 7 & 1 = 8; chet, where His Oneness spreads out and is manifest to the four directions (dalet) (Shulchan Aruch; Orech Chaim 61:5).
On a deeper level, the individual soul (1), when the time is deemed appropriate descends through the same basic (8) levels or dimensions of reality until it enters into a body in this physical world and begins to move about and manifest in all (4) directions.
Therefore, saying the Shema is not only a potent prayer to draw down God’s Oneness into this material world, but is also a powerful practice for drawing down the soul’s heavenly root into active consciousness.
That is why the numerology of Echad= 13, the union of the 13 Tribes as well as the same numerology as the Ahava- love. True love is uniting opposites and is the ultimate Yichud, that is why the first word after the Shema affirmation is V’Ahavata- “you shall love”.
It is fascinatingly interesting that throughout the morning prayers, the theme of the number 13 appears. After the first section of Korbanot, there is a Mishnah of Rabbi Yishmael who details the 13 ways the Torah is interpreted. In the beginning of the second section- P’sukei D’zimrah, the “Baruch She’amar” consists of 13 “baruch”- blessed. At the end of that section, “Yishtabach”, there are 13 praises. And finally, the Amida -The 18 (or 19) begins with the first 3 blessings praising the creator and the last 3 giving thanks. The middle section of the Amida has 13 blessings where the individual needs prays for their needs.
There are two level -אחד one and יחיד- singular. Echad -one, means that there is 2 and 3, etc. Whereas, Yachid means singular, that there is only him.
Although, it is true that G-d’s reality is unchanged and that he is really singular, the purpose of creation is to reveal G-0d within the multiplicity.
In other words, our purpose in life is to reveal how everything is one and that there is “no one but him”.
Prayer is the way we do this. Through prayer, we become connected to the intention of creation, unifying our inner world and the world around us to become bound with the creator, merging opposites and drawing down life energy for ourselves and the world.
Excerpt from the 5 part "Essence Of Prayer" Course https://www.livekabbalah.com/p/Enroll
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