The mystery cults were the pagan secretive cults that flourished during the rise of Christianity. Many Christian fathers used mystery language or adhered to mystery teachings. Christian similarities to mystery cults might even explain Christianity’s rapid expansion. But several teachings of the mystery cults tainted Christianity and have stayed ever since. It is important to understand who the mystery cults were and what they taught.
Plato details one of the primary goals of the mystery cults in Phaedo:
And I conceive that the founders of the mysteries had a real meaning and were not mere triflers when they intimated in a figure long ago that he who passes unsanctified and uninitiated into the world below will live in a slough, but that he who arrives there after initiation and purification will dwell with the gods. For “many,” as they say in the mysteries, “are the thyrsus bearers, but few are the mystics,”-meaning, as I interpret the words, the true philosophers.
Here Plato is saying that the mystery cults had one of their primary objectives to “purify” the soul. He explains how this is achieved:
But he who is a philosopher or lover of learning, and is entirely pure at departing, is alone permitted to reach the gods. And this is the reason… why the true votaries of philosophy abstain from all fleshly lusts, and endure and refuse to give themselves up to them-not because they fear poverty or the ruin of their families, like the lovers of money, and the world in general; nor like the lovers of power and honor, because they dread the dishonor or disgrace of evil deeds.
The first step is poverty, throwing off the things of this world. The next step is casting off the body:
…I will tell you, he said. The lovers of knowledge are conscious that their souls, when philosophy receives them, are simply fastened and glued to their bodies: the soul is only able to view existence through the bars of a prison, and not in her own nature; she is wallowing in the mire of all ignorance; and philosophy, seeing the terrible nature of her confinement, and that the captive through desire is led to conspire in her own captivity… philosophy shows her that this is visible and tangible, but that what she sees in her own nature is intellectual and invisible…
…because each pleasure and pain is a sort of nail which nails and rivets the soul to the body, until she becomes like the body, and believes that to be true which the body affirms to be true; and from agreeing with the body and having the same delights she is obliged to have the same habits and haunts, and is not likely ever to be pure at her departure to the world below, but is always infected by the body; and so she sinks into another body and there germinates and grows, and has therefore no part in the communion of the divine and pure and simple.
A final step, as detailed by Plotinus and alluded to in Plato, is an upward ascent of the soul. But I will cover that later.
A key teaching of the mystery cults was that our human bodies are prisons. The goal of true religion is to cast off the body, disdain fleshly desires, and return to a state of purity. To the early Christians, this took the form of chastity or asceticism. While, not popular in modern Christianity, it is important to note that all early Christian fathers were tainted with these particular teachings. For example, Origen castrated himself and Augustine considered his conversion from sex as his conversion to Christianity. While these particular doctrines are not strong in modern culture, it is important to realize that more dangerous mystery cult teachings have persisted (notably the teachings about the character of God).