Gnosticism (from the Greek word gnōsis, meaning 'knowledge') was a mystical belief system that is still greatly misunderstood. Many errors regarding its origins and teachings are perpetuated to this day.
Gnosticism emerged from within the Christian community during the 2nd Century AD and is therefore a Christian heresy, not a pagan intruder.
There is no evidence of any pre-Christian Gnostic literature or oral tradition (Gnostic writings all date from the Christian era) and no belief system resembling Gnosticism in the 1st century AD.
Gnostics claimed to be heirs of secret traditions passed down from Jesus through a clandestine tradition.
One of their earliest leaders was a heretic called Valentinus. His followers said he had been taught by a fellow Gnostic called Theudas, whom they believed had been instructed by the apostle Paul.