Kabbalah — from the Hebrew qibel, to receive — is the mystical tradition of Judaism, concerned with the hidden dimensions of Torah, the nature of God (Ein Sof — the Infinite), the structure of creation and the path of the soul's return to its divine source. It is simultaneously a cosmological system, a psychology of the soul, a method of biblical interpretation and a practical path of spiritual development.
The two foundational texts of Kabbalah are the Sefer Yetzirah (Book of Formation — perhaps 3rd-6th century CE) and the Zohar (Book of Splendour — compiled in 13th-century Spain, attributed to Rabbi Shimon bar Yochai of the 2nd century). The Zohar is the central text of classical Kabbalah — a vast mystical commentary on the Torah that elaborates the nature of the divine, the structure of the soul and the mechanics of creation through the Ten Sephiroth of the Tree of Life.
The Kabbalistic understanding of the soul is inseparable from the Kabbalistic understanding of God. The soul is not a separate created being that God governs from outside — it is a portion of the divine itself, temporarily clothed in matter. The purpose of incarnation is not punishment or testing but the fulfilment of tikkun olam — the repair of the world — through the conscious alignment of the individual soul with its divine source. Every soul carries a unique portion of the divine light, and every act of love, justice and wisdom performed in the world repairs a fragment of the primordial fracture through which that light was scattered.