The tzimtzum or tsimtsum is a term used in the Lurianic Kabbalah to explain Isaac Luria's doctrine that God began the process of creation by "contracting" his Ohr Ein Sof in order to allow for a "conceptual space" in which finite and seemingly independent realms could exist. This primordial initial contraction, forming a ḥalal hapanuy "vacant space" into which new creative light could beam, is denoted by general reference to the tzimtzum. In Kabbalistic interpretation, tzimtzum gives rise to the paradox of simultaneous divine presence and absence within the vacuum and resultant Creation. Various approaches exist then, within Orthodoxy, as to how the paradox may be resolved, and as to the nature of tzimtzum itself.

Lurianic Kabbalah is a school of Kabbalah named after Isaac Luria (1534–1572), the Jewish rabbi who developed it. Lurianic Kabbalah gave a seminal new account of Kabbalistic thought that its followers synthesised with, and read into, the earlier Kabbalah of the Zohar that had disseminated in Medieval circles.