Kabbalah (Hebrew: קַבָּלָה Qabbālā, literally "reception, tradition") is an esoteric method, discipline and school of thought in Jewish mysticism. A traditional Kabbalist is called a Mekubbal (מְקוּבָּל‎ Məqūbbāl "receiver"). The definition of Kabbalah varies according to the tradition and aims of those following it, from its origin in medieval Judaism to its later adaptations in Western esotericism (Christian Kabbalah and Hermetic Qabalah). Jewish Kabbalah is a set of esoteric teachings meant to explain the relationship between the unchanging, eternal God—the mysterious Ein Sof (אֵין סוֹף‎, "The Infinite")—and the mortal, finite universe (God's creation). It forms the foundation of mystical religious interpretations within Judaism.

Jewish Kabbalists originally developed their own transmission of sacred texts within the realm of Jewish tradition and often use classical Jewish scriptures to explain and demonstrate its mystical teachings. These teachings are held by Kabbalists to define the inner meaning of both the Hebrew Bible and traditional rabbinic literature and their formerly concealed transmitted dimension, as well as to explain the significance of Jewish religious observances.

Traditional practitioners believe its earliest origins pre-date world religions, forming the primordial blueprint for Creation's philosophies, religions, sciences, arts, and political systems. Historically, Kabbalah emerged from earlier forms of Jewish mysticism, in 12th- to 13th-century Spain and Southern France, and was reinterpreted during the Jewish mystical renaissance in 16th-century Ottoman Palestine. The Zohar, the foundational text of Kabbalah, was composed in the late 13th century. Isaac Luria (16th century) is considered the father of contemporary Kabbalah; Lurianic Kabbalah was popularised in the form of Hasidic Judaism from the 18th century onwards. During the 20th century, academic interest in Kabbalistic texts led primarily by the Jewish historian Gershom Scholem has inspired the development of historical research on Kabbalah in the field of Judaic studies.