Gnosticism is an ancient religious movement that emphasizes esoteric knowledge as the path to spiritual enlightenment. It teaches that the material world is flawed or evil, created by a lesser deity, and that true salvation comes from escaping it. Gnostics believe in a higher, unknowable God and view Jesus as a divine figure who imparts secret wisdom. This movement was most prominent in the early centuries of Christianity but was considered heretical by mainstream Christian authorities.