Uroboros

In the Hermetic philosophy that arose in Hellenistic Egypt, the ouroboros became a symbol of the underlying unity of spirit. The Gnostics, who believed the world to be at the center of the universe, believed that the ouroboros, or world serpent, marked the boundary between the world and the pleroma of heaven. Some Gnostics equated the world serpent with the evil demiurge (or Satan) who created the world and guards the gateway of escape. Gnostics equated the demiurge with the God of the Old Testament, the Alpha and Omega (the letter omega is similar in form to the Egyptian hieroglyph shen).