Let me begin by laying out the downside of the term syncretism. Syncretism seems to propose two (or more) discrete religious systems, like Christianity and Heathenism, or Judaism and Hellenism, or Persia and Greece. And this is problematic because none of these systems or traditions was ever discrete and pure. Syncretism thus relies on a romantic fantasy of the pure culture: apostolic Christianity, biblical or rabbinic Judaism, Pharaonic Egypt.
Syncretism, then, implies mixtures that are ad hoc, base and commercial, intellectually unsophisticated, travesties and distortions of those pure traditions. The pure religions of Judaism, Christianity, and Platonic Hellenism gain only cheap mystification, even pollution, when mixed with Persian or Berber traditions. Thus the very epitomes of syncretism in Late Antiquity can be found in the Greek Magical Papyri, in Mystery Cults like Mithraism, in pseudo-intellectual ritual schemes like Hermeticism and Gnosticism, and in those latter-day Christianities that used to strike...
University of California Press