those men who established the mysteries Orphic mysteries were not unenlightened, but in reality had a hidden meaning when they said long ago that whoever goes uninitiated and unsanctified to the other world will lie in the mire but he who arrives there initiated and purified will dwell with the gods.
Edinger, via Plato’s Phaedo, argues that the Orphic Mysteries encode a genuine philosophical doctrine of psychic purification that anticipates the Socratic programme of katharsis.
, The Psyche in Antiquity, Book One: Early Greek Philosophy From Thales to Plotinus, 1999thesis