Derush ha-Tanninim (Essay on the Dragons) is Nathan of Gaza's foundational cosmological text, composed in 1665 as the theological framework for the Sabbatian movement. It presents a radical reinterpretation of Lurianic cosmology, positing the existence of primordial dragons (Tanninim) within the vacated space (Tehiru) left after the divine contraction (Tzimtzum). These dragons represent unrectified forces that precede and condition the entire process of emanation. This is the first complete English translation of a text that has never been fully rendered in any Western language.