Gnosticism (from Ancient Greek γνωστικός (gnōstikós) 'having knowledge'; Koine Greek: [ɣnostiˈkos]) is a collection of religious and philosophical ideas and systems that coalesced in the late first century AD among sects of early Christianity and other faiths. It is not a singular, homogeneous tradition or religion, but an umbrella term used by modern scholars to describe different groups and beliefs that shared certain characteristics. These diverse Gnostic groups generally emphasized personal spiritual knowledge (gnosis) above the authority, traditions, and proto-orthodox teachings of organized religious institutions. The Gnostic worldview typically distinguished between a hidden, uncorrupted supreme being and a flawed demiurge responsible for creating material reality. Gnostics held this material existence to be evil and believed the principal element of salvation was direct knowledge of the supreme divinity, attained via mystical or esoteric insight. Many Gnostic texts deal not in concepts of sin and repentance, but with illusion and enlightenment.
Although the exact origins of Gnosticism cannot be traced, Gnostic writings flourished among certain Christian groups in the Mediterranean during the second century. In the Gnostic Christian tradition, Christ was seen as a divine being that had taken human form in order to lead humanity back to recognition of its own divine nature. Judean–Israelite Gnosticism, including the Mandaeans and Elkesaites, blended Jewish-Christian ideas with Gnostic beliefs focused on baptism and the cosmic struggle between light and darkness. Syriac–Egyptian groups like Sethianism and Valentinianism combined Platonic philosophy and Christian themes, seeing the material world as flawed but not wholly evil. Other traditions include the Basilideans, Marcionites, and Thomasines. Manichaeism, which adopted Gnostic concepts such as cosmic dualism, emerged as a major religious movement in the third century, briefly rivaling Christianity.
