qlippoth conceal this holiness, and are therefore synonymous with what runs counter to Jewish thought, like idolatry, impurity, rejection of Divine unity (dualism), and with the Sitra Achra, the perceived realm opposite to holiness. Much like their holy counterparts, qlippot emerge in a descending seder hishtalshelus (Chain of Being) through Tzimtzum (God's action of contracting His Ohr Ein Sof, "infinite light", in order to provide a space for Creation). Kabbalah distinguishes between two "realms" in qlippot, three completely impure qlippot ( haṭmēʾōṯ, literally "the unclean [ones]") and the remainder of intermediate qlippot ( nōgah, literally "light"). The qlippot nogah are "redeemable", and can be refined and sublimated, whereas the qlippot hatme'ot can only be redeemed by their own destruction. Similar to a certain interpretation of the Kabbalistic Tree of Life, the qlippoth are sometimes imagined as a series of concentric circles which surround not just aspects of God, but also one another. Their four concentric terms derived from various phrases used in Ezekiel's famous vision of the Throne of God (Ezekiel 1:4), itself the focus of a school of Jewish mystic thought, "And I looked and behold, a whirlwind came out of the north, a great cloud, and a fire infolding itself, and a brightness was about it..." The whirlwind, great cloud, and infolding fire are associated with the aforementioned three "impure" qlippot, with the "brightness" associated with the "intermediate" qlippot. In medieval Kabbalah, it was believed that the Shekhinah (God's presence) is separated from the Sefirot by man's sins, while in Lurianic Kabbalah it was believed the Shekhinah was exiled to the qlippot due to the "shattering" of Divinity into Tohu and Tikun, which is a natural part of its cosmological model of Creation. This in turn causes the Sephirot's various "Sparks of Holiness" to be exiled in the qlippot as well, thereby causing these respective qlippoth to manifest as either the qlippot nogah or qlippot hatme'ot. From there, the qlippot nogah would be redeemed through the observance of mitzvah, whereas the qlippot hatme'ot would be indirectly "redeemed" through abiding by the negative prohibitions put forth by the 613 commandments. In addition to righteous living, genuine repentance also allows the qlippot to be redeemed, as it retrospectively turns sin into virtue and darkness into light, and thus deprives the qlippot of their vitality. According to Lurianic Doctrine, when all the Sparks of Holiness are freed from the qlippot, the