This is the name for the first and lowest of the five levels (and corresponding lights) of the soul, nefesh, ruaḥ, neshama, ḥaya, and yeḥida. These five levels of the soul correspond to the five primary sefirot, of 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. The nefesh corresponds to and is the light that belongs to the sefira of Malkhut and the world of Asiya, and it is the first aspect of the soul that is illuminated within a person or an aspect of reality.
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