Plutarch is for us the chief mouthpiece of the theory that all religions are fundamentally one, under different names and with different practices. For him and Maximus of Tyre ‘the gods’ are symbolic representations of the attributes of a Deity who is in his inmost nature unknowable. Maximus and Dion Chrysostom are ‘modernist’ in their views about myth and ritual; Philostratus and Ælian are genuinely superstitious. The Hermetic writings are good examples of the Plutarchian theory. They show, however, that the combination of philosophic monotheism with popular polydaemonism was becoming difficult, though the writers are equally anxious to retain both, as indeed the Neoplatonists were. Syncretism was easier when the gods were regarded as cosmic energies, or when their cults were fused in the popular worship of the sun and stars.
Dionysus and Orpheus were two nearly connected forms of the Sun-god, and the worship of both was influenced by the rites of the Thracian Sabazius. The central act of both mysteries was the rending in pieces of the god or hero, the lament for him, his resurrection, and the communion of his flesh and blood as a ‘medicine of immortality.’ The Egyptian Osiris had also been torn in pieces by his enemies; his resemblance to Dionysus was close enough to tempt many to identify them. In the Egyptian worship the doctrine of human immortality had long been emphasised, and this was now the most welcome article of faith everywhere. It was easy to fuse these national mystery-cults with each other because at bottom they all symbolised the same thing—the hope of mystical death and renewal, the death unto sin and the new birth unto righteousness, based on the analogy of nature's processes of death and rebirth.
While Judaism was purging itself from its Hellenistic element and relapsing into an Oriental religion, the bond of union in a people who were determined to remain aliens in Europe, Christianity was developing rapidly into a syncretistic European religion, which deliberately challenged all the other religions of the empire on their own ground and drove them from the field by offering all the best that they offered, as well as much that they could not give. It was indeed more universal in its appeal than any of its rivals. For Neoplatonism, until it degenerated, was the true heir of the Hellenic tradition, and had no essential elements of Semitic origin. Christianity had its roots in Judaism; but its obligation to Greek thought began with St. Paul, and in the third century ‘philosophic’ Christianity and Platonism were not far apart.
The real quarrel between Neoplatonism and Christianity in the third century lay in their different attitudes towards the old culture. In spite of the Hellenising of Christianity which began with the first Christian missions to Europe, the roots of the religion were planted in Semitic soil, and the Church inherited the prejudices of the Jews against European methods of worship.
Hellenism was vitally connected with polytheism, and with the sacred art which image-worship fostered. These things were an abomination to the Jews, and therefore to the early Christians. We, however, when we remember later developments, must take our choice between condemning matured Catholicism root and branch, and admitting that the uncompromising attitude of the early Church towards Hellenic polydaemonism was narrow-minded.
Porphyry made a very dignified protest against the charge that the Pagans actually worship wood and stone. ‘Images and temples of the gods,’ he says, ‘have been made from all antiquity for the sake of forming reminders to men. Their object is to make those who draw near them think of God thereby, or to enable them, after ceasing from their work, to address their prayers and vows to him. When any person gets an image or picture of a friend, he certainly does not believe that the friend is to be found in the image, or that his members exist inside the different parts of the representation. His idea rather is that the honour which he pays to his friend finds expression in the image. And while the sacrifices offered to the gods do not bring them any honour, they are meant as a testimony to the good-will and gratitude of the worshippers.’ The early Christian horror of idolatry was a legacy from the Jews, who were, on the aesthetic side, too unimaginative to understand a mode of worship which for other nations is natural and innocent.
-- William Ralph Inge, The philosophy of Plotinus