 A reoccurring theme in Del Medigo’s physical works is the nature of Divine causality. This is the main theme of both the Quaestio de efficientia mundi as well as the De primo motore. Divine causality was a popular theme throughout the Middle Ages and the Renaissance, and by participating in this discussion—clarifying and endorsing Averroes’ view on the matter—Del Medigo is again shown to be participating in what was essentially a Christian scholastic debate (Licata 2013a: 61; Montada 2013: 158). The Quaestio de efficientia mundi, composed in 1480 at the request of Girolamo Donato, asks whether God, the prime mover, is only the cause of the celestial bodies’ movement, or of their essence and existence as well (Licata 2013c: 59–60). In his discussion Del Medigo is relying, among other sources, on the short, middle and long commentaries on the Metaphysics as well as on Averroes’ De substantia orbis. Del Medigo himself translated the introduction of book XII of the Metaphysics from Hebrew into Latin (Montada 2013: 164), and his tendency to include in his original compositions citations from treatises which he himself translated is characteristic of Del Medigo’s work in general (see Engel: 2017: 18). At Del Medigo’s own admission, the Quaestio de efficientia mundi consists of arguments collected from the works of Averroes, leading to the conclusion that God is not only the mover of the celestial spheres, but their efficient cause as well. Here Del Medigo’s discussion is echoing an internal Averroist debate, arguing against the interpretation of John of Jandun, who held that God is only the final cause of the universe, not its efficient cause (Licata 2013a: 60). God is the efficient cause of the spheres, Del Medigo explains, not by creating them ex nihilo, but by guaranteeing their movement, which in turn constitute their being. He therefore endorses a qualified sense of efficient causality, according to which whoever grants a thing its essence—as God eternally grants the spheres their movement—may be considered an efficient cause in congruence with Averroes’ position as expounded in works such the Destructio destructionum and De substantia orbis. (Del Medigo 1480a: f. 140r; Licata 2013c: 62–63; Licata 2013a: 53–54). Closely related to the Quaestio de efficientia mundi is Del Medigo’s De primo motore, written around the same time. In that work, Del Medigo arrives at the same conclusion, i.e., God as the efficient as well as the formal and final cause of the universe. Creation is interpreted as eternal act of creation, and the eternity of the world becomes compatible with the existence of a creator (see Del Medigo 1480a: f. 134r; Licata 2013a: 57, 62):