Theurgy, along with Neoplatonism, are recognizable roots of the ceremonial magic of the Middle Ages and the Renaissance, which are themselves the roots of the post-Enlightenment ceremonial magic that still exists today. Therugy was founded by Julianus, the author of the famous
Chaldean Oracles. Julianus lived during the time of the Roman Emperor Marcus Aurelius and he was the first person known to be described as a θεουργός, a therugos, a term he himself coined to distinguish himself the θεολόγοι, theologoi. Julianus differentiated between the two as theologoi only
spoke about the gods, a therugos actually worked with them to practical effects Both of these would have been differentiated from
magia, which by this time would have negative connotations. By the beginning of the common era “magic” would be something that “other people” did while “theurgy” would be what our people did while the practice of the two would in actuality be nearly identical.
We can, as Proclus did before us, define theurgy as “a power higher than all human wisdom, embracing the blessings of divination, the purifying powers of initiation, and in a word all the operations of divine possession” (qtd in Dodds, 61). More simply, E.R. Dodds defines theurgy as magic for a religious purpose (ibid). While Dodds says that this should be differentiated from magic, which uses divine names and religious formulae for mundane or profane purposes the actual differentiation, as I mentioned above, is much more difficult. Thus we see in De mysteriis that divination is a part of theurgic practice and the therugic rituals attributed to Proclus included weather manipulation and the evocation of a vision of the goddess Hecate. Overall, the actual practice of theurgy appears to be similar to the practice of magic and has two distinguishable branches: τελεστική (telestika) and the use of a trance medium. The first was concerned primarily with the consecration and animation of magic statues to gain oracles from them. This practice was passed onto medieval magicians, against which a Papal Bull was eventually addressed. Dodds also suggests that this practice may have influenced medieval alchemists into trying to create homunculi, or artificial human beings.
Eventually therugy would be combined with Neoplatonism. However this would not happen through the founder of Neoplatonism, Plontinus, but through one of his students, Porphyry. It was not that Plontinus disdained therugy, instead it seemed that he was simply unaware of Julianus, his writings or his ideas in general. Before Porphyry, however, Neoplatonism was largely what Julianus would have called theologoi; i.e. a theological philosophy. While technically a form of paganism and polytheistic in nature, Neoplatonism also posited a monistic reality that everything, including the gods, was a manifestation and reflection of. Neoplatonic theology, which would eventually find its way into the Hermetic writings of the time, posited a series of emanations that moved from the singular divinity, called the Good in Hermetic literature, to Mind, to Soul and finally to Nature, with humanity partaking of all of these. An identical schema can be found in both the Corpus Hermeticum and the Asclepius, two important Hermetic texts.
Thus here we have the very beginnings of what we would come to know as ceremonial magic. Until the late middle ages these two were in fact the most influential parts of ceremonial magic. They would eventually be combined in late Antique period Hermeticism and then re-evaluated in medieval and Renaissance Hermeticism. Eventually these three foundational philosophies and practices would be merged with Christian derivations of Jewish Kabbalah. Even with the importance of tarot, 18th and 19th century Egyptomania and the post-Christian Qabalah of the Golden Dawn, these four legs of the magical throne remain the most important parts of ceremonial magic and can be found, though it is often obscured, in modern magical practices today, both in the realms of ceremonial magic and in the magical practices of modern Paganism.
Dodds, E. R. “Theurgy and its Relationship to Neoplatonism.” The Journal of Roman Studies Vol. 31, 1947. 55-69.
Janowitz, Naomi. Icons of Power: Ritual Practices in Late Antiquity. University Park, PA: The Pennsylvania State University Press, 2002.