Ohr ("Light" Hebrew: אור; plural: Ohros/Ohrot "Lights" אורות) is a central Kabbalistic term in Jewish mysticism. The analogy of physical light is used as a way of describing metaphysical divine emanations. Shefa (שפע "flow" and its derivative, Hashpoah "Influence" השפעה) is sometimes alternatively used in Kabbalah, a term also used in Medieval Jewish philosophy to mean divine influence, while the Kabbalists favour Ohr because its numerical value equals Raz ("mystery"). It is one of the two main metaphors in Kabbalah for understanding God, along with the other metaphor of the human soul-body relationship for the sefirot.

The metaphorical description of spiritual divine creative flow, using the term for physical "light" perceived with the eye, arises from analogous similarities. These include the intangible physicality of light, the delight it inspires and the illumination it gives, its apparently immediate transmission and constant connection with its source. Light can be veiled ("tzimtzum"-constrictions in Kabbalah) and reflected ("an ascending light from the Creations" in Kabbalah). White light divides into seven colours, yet this plurality unites from one source. Divine light divides into the seven emotional sefirot, but there is no plurality in the Divine essence. The term Ohr in Kabbalah is contrasted with ma'ohr, the "luminary", and kli, the spiritual "vessel" for the light.

As a metaphor it also has its limitations. Divinity can only be understood from analogous comparisons to the spatial and temporal phenomena we understand. Once these images are grasped, Kabbalah stresses the need to then attempt to transcend them by understanding their deficiencies. Among the limitations of the central metaphor of "light" are the physical inability of the luminary to withhold its radiance, the fulfilment of purpose the light gives the luminary, and the categorical differentiation between the source and its light. For God, the Creation metaphorically "arose in the Divine Will" and was not impelled. The emanation of Creation fills no lack in the perfection of God. The distinction between the Divine light (beginning with the Ohr Ein Sof - the primordial "Infinite Light", and subsequently the ten sefirot emanations) and the Divine Ein Sof or divine source appears only relative to Creation. From God's perspective, Scripture states "For I, the Eternal, I have not changed". From the perspective of God's self-knowledge, the emanations remain completely united and nullified to their source. This answers early Rabbinic criticism of dualism in Kabbalah. The term in Kabbalah and Hasidic philosophy for this nullification is bittul. In devekut or daily spiritual life, it inspires the mystical humility of nullification of the ego.