Ḥaya is the name of the fourth 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. They also correspond to 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 ḥaya is the light that corresponds to the sefira of Ḥokhma and the world of Atzilut, and it illuminates the body of a person or a level only after the illumination of the three lower levels of the soul, which are nefesh, ruaḥ, and neshama.
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