TEURGY (θεουργικά). — From θεός “god” and έργον “work,” it signifies “divine operation,” almost always of a magical character, performed by one invested with divine power, that is, by the *teurgus*, an epithet first assumed by a certain Julian, son of the Chaldean Julian, who lived in the time of Marcus Aurelius and is presumed to be the author of the *Chaldean Oracles*, a versified composition in which the mystical-astral doctrines of Babylonian science are fused with the philosophical doctrines of Greece.
While Neoplatonism, with Plotinus and in part with his disciple Porphyry, had maintained itself in a noble sphere of mystical philosophy, with Iamblichus, disciple of Porphyry and author of the *De mysteriis Aegyptiorum*, it descended to the level of magic, claiming to achieve union with the Supreme Being through magical means, especially sacrifice, capable of elevating man toward the One despite his moral inferiority, and divination, whether divine, occurring through sacred sleep, or demonic, attained by means of amulets and talismans.
The *teurgus* can free himself from all ties to matter, rendering himself insensible to fire or wounds, can rise into the air, transfigure himself, and read the future. The *teurgus*, in short, thanks to his commerce with the divine world, can command the things of the world without limit (Iamblichus, *De myst.*, 7, 4; 96, 9). The *teurgus* gave himself this epithet to distinguish himself from the magician, since he claimed to be the confidant of celestial spirits and asserted that his miracles occurred through simple faith and trust in God, not through the lots and incantations of a sinful curiosity that they call magic or, in a more detestable name, *goetia* (St. Augustine, *De civ. Dei*, X, 9); with this word (γὰςτελὸς τὰ γνόδία = “I groan, I lament”) they meant the lugubrious incantations that preceded the operations of diabolical magic.