Sethianism is an ancient Gnostic belief system that emerged in the early centuries of Christianity. It is named after Seth, the third son of Adam and Eve, whom followers regarded as a divine figure. Sethians believed in a complex cosmology involving a supreme, unknowable God and a series of lesser divine beings, or aeons, who created the material world. Central to Sethianism is the idea of gnosis, or spiritual knowledge, which allows individuals to transcend the material realm and return to the divine source. Sethian texts, such as the Apocryphon of John, explore themes of creation, redemption, and the nature of the divine, emphasizing the importance of inner enlightenment.