The Albigensians in the south of France during the Middle Ages were gnostics. Gnosticism has survived even to this day, if you count all Christians who believe that they have "special knowledge" that departs from the canonical scriptures. That gnostic vice is the same vice that resulted in Adam's fall. "Eat of this tree and ye shall be as gods!" Orthodox Christianity has never been about special knowledge.
Any talk about "special knowledge" turns religion into sorcery.