The name of the fifth and highest of the five levels of the soul,nefesh, ruaḥ, neshama, ḥaya, and yeḥida. These five levels of the soul correspond to the five primary sefirot, Keter, Ḥokhma, Bina, Tiferet, and Malkhut, as well as the five worlds, Adam Kadmon, Atzilut, Beria, Yetzira, and Asiya. The concept of the five levels of the soul relates to five qualities of supernal light which illuminate people as well as the levels of broader reality. Yeḥida is the light that parallels the sefira of Keter and the world of Adam Kadmon, and it illuminates the body of a person or a level only after the illumination of the four lower levels, nefesh, ruaḥ, neshama, and ḥaya.
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