Theurgy, theourgia, was defended by Iamblichus against Porphyry: the soul cannot reach the divine by thought alone, but needs rites, symbols and prayers that the gods themselves have given. Proclus practised it. Dionysius the Areopagite transposed the idea into Christian sacramental theology.
Theurgy
Divine work: the Neoplatonic ritual practices by which the soul is united with the gods.