Gnosticism, a system of belief which attempted to combine Christian doctrines with elements derived from Greek philosophy, Judaism, and Oriental religions. The Gnostics were so called because they laid claim to knowledge (Greek gnosis) of a special kind concerning the mysteries of the Divine nature. Gnosticism reached its most vigorous state about the middle of the 2nd century, and died out in the latter part of the 4th century. Its main principles were everywhere the same, but the doctrines based upon them differed considerably in the various sects. The following were the cardinal points of the system: - There is one Eternal and Supreme Deity, who dwells apart from the hyle or material world in the midst of a pleroma or fulness of light. From Him there emanate numerous AEons, representing for the most part certain attributes of Deity, such as Wisdom, Truth, and Might. The AEons partake in a varying degree of the Divine nature, and low down in the scale is the Demiurgus, the creator of the visible world, who was identified with Jehovah, the God of the Old Testament. Those Gnostics who were influenced by Zoroastrian doctrines held that the Demiurgus is the evil principle in the universe, and that he is engaged in a perpetual conflict with the Supreme Deity, the source of all good. All the schools recognised a three-fold division of mankind - the "spiritual," who have an insight into the Divine nature; the "terrestrial," who are under the dominion of matter; and a third class, who are subject to the laws imposed by the Demiurgus for the attainment of his own ends. As matter is essentially evil, there is no resurrection of the body. For the same reason the doctrine of the Incarnation, which involved the combination of the divine nature with a material body, was rejected, and either the divine or the human attributes of Christ were explained away. The Ebionites, Basilidians, Carpocratians, and Cerinthians held that He was a man, and that the Divinity descended upon Him at His baptism in the form of a dove, leaving Him before the crucifixion. The Saturninians, Encratites (followers of Tatian), and Marcionites, on the other hand, maintained that the body of Christ was an unsubstantial phantom; while the Bardesanians and Valentinians asserted that it was composed of the same elements as those of the angels. The redemption was represented as a communication to mankind of the gnosis, which delivered the spiritually-minded from the bondage of the material world. These general principles gave rise to two widely different views of conduct. Some endeavoured by a severely ascetic life to maintain a rigid self-control, which would deliver them from the influence of the hyle or the Demiurge, while others held that for those endowed with gnosis all actions were indifferent, and expressed their contempt for matter by giving free vent to their animal appetites. In so far as they accepted the Old Testament, the Gnostics interpreted it in a symbolical sense. For the most part, however, they refused to recognise it at all, and they gradually rejected the greater part of the New Testament also, substituting certain apocryphal books and spurious gospels of their own.