There were many groups of Christians in the first few centuries. One important group — the Sethian Gnostics — aspired to mystical knowledge that they interpreted through wisdom, stories, themes (in particular, Genesis), and myths of various religious and philosophical traditions in order to find their way back to the Godhead. The fifth chapter of Genesis details the genealogy of the Hebrew patriarchs, among them a son of Adam. When Adam was 130 years old, he bore a son “in his own likeness, and after his image; and called his name Seth” (Genesis 5:3). The Sethians saw Seth as a savior figure much as Christians viewed Christ. The Sethians began as a Messianic religion (with the expectation of the coming of a savior/messiah) much as the Jewish Christian movement did. Contact with the earliest forms of Christianity brought Christian elements into the Gnostic Sethians' belief and practices.
Gnostic Sethian mythology features a number of characters who play out roles in an epic story that serves as a “pre-story” to Genesis. Gnostics did not believe that human sin brought humanity into enslavement in the material world, but rather that this enslavement was the fault of the creator. The Sethian myth attempts to offer a Gnostic explanation of the downward shift from God to human, from Spirit to matter.
Sethian Gnosticism is so-called because of references to Seth, the child of Adam and Eve, one who provided special knowledge. Sethian Gnostic writings include Zostrianos, The Three Steles of Seth, Apocalypse of Adam, Allogenes, The Reality of the Rulers, The Gospel of the Egyptians, The Apocryphon of John, The Threefold First Thought, and The Thunder, Perfect Mind.
Several Gnostic texts share a cluster of common beliefs that relate to Sethian mythology:
The Holy Trinity is made up of the Invisible Spirit (Father), Barbelo (Mother), and Son (the Demiurge).
Gnostics have gnosis that they are collectively the spiritual kernels or seeds of Seth.
Seth is the Savior of his seed.
The Demiurge Yaldabaoth attempts to destroy the seed of Seth.
There are three Ages, and the Savior comes in each Age.
One version of the Sethian myth opened with an Aeon named Barbelo. This Aeon was perhaps the original emanation of God and possessed both a masculine and feminine side. Barbelo was a kind of master parent of all the other emanations or Aeons, and they, too had masculine and feminine aspects. And so, each emanation split off into more emanations that continued the process. All of these emanations, dividing and multiplying like a cell undergoing mitosis, fragmented God until the primordial universe became unstable. That's when the Aeon Sophia appeared in the story.
Sophia means “wisdom” in Greek; as her name implied, she wisely considered her position so far removed from the Godhead and pondered on how to get back to the center of divine nature closest to God. She decided to imitate God's original action of emanating. She did not seek permission. Her act of creating a copy of herself caused something of a crisis to occur within the Pleroma and as a result, the Demiurge known as Yaldabaoth (sometimes pictured as a serpent with a lion's head) was born of Sophia. She created a throne for him and wrapped him in a resplendent cloud, where the monstrous being lived, isolated and without knowledge of the higher realms — of the Pleroma Reality.
How was Yaldabaoth similar to Yahweh, God of the Hebrews?
Yaldabaoth, ignorant of any other god, declares some variation of: “I am a jealous God; there is no God but me.” The Hebrew's Yahweh makes a similar statement in Exodus 20:4–5. The Gnostics accorded Yaldabaoth and Yahweh the status of inferior gods.
Yaldabaoth stole some power from his mother to create the material universe. Unknowingly, he created a carbon copy of the Pleroma, but his world simply reflected reality. It wasn't the real deal. He, as inferior creator, created the imperfect physical world and the beings in it mirrored those above. In that way, his mother's power became encapsulated into human forms and humans became ensnared in the material universe. This sets the stage for Yaldabaoth to create man in the image of God.
One version of the Gnostic myth is that God tricks Yaldabaoth to transfer some of his mother Sophia's power into the inanimate Adam, who at that point had no spirit. This breathing of life into Adam was the initial step in making all humans animate and more powerful than Yaldabaoth's beings or cosmic forces. Those beings then banished Adam into the lowest realms of matter. But all is not lost, because God takes pity on Adam and inspires him with a divine thought on how to extricate himself from matter and ascend to his true home.