Neoplatonism and Gnosticism

Gnosticism refers to a collection of religious groups originating in Jewish religiosity in Alexandria in the first few centuries CE.Neoplatonism was a school of Hellenistic philosophy that took shape in the 3rd century, based on the teachings of Plato and some of his early followers. While Gnosticism was influenced by Middle Platonism, neo-Platonists from the third century rejected Gnosticism.

Gnosticism originated in the late first century CE in nonrabbinical Jewish sects and early Christian sects, and many of the Nag Hammadi texts make reference to Judaism, in some cases with a violent rejection of the Jewish God.

Sethianism may have started as a pre-Christian tradition, possibly a syncretic Hebrew Mediterranean baptismal movement from the Jordan Valley, with Babylonian and Egyptian pagan elements, and elements from Hellenic philosophy. Both Sethian Gnostics and the Valentinian Gnostics incorporated elements of Christianity and hellenistic philosophy as it grew, including elements from Plato, Middle Platonism and Neo-Pythagoreanism.

Earlier Sethian texts such as Apocalypse of Adam show signs of being pre-Christian and focus on the Seth of the Jewish bible. Later Sethian texts are continuing to interact with Platonism, and texts such as Zostrianos and Allogenes draw on the imagery of older Sethian texts, but utilize "a large fund of philosophical conceptuality derived from contemporary Platonism, (that is late middle Platonism) with no traces of Christian content."

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