The basic doctrine of Gnosticism was that matter is essentially evil and spirit is essentially good. The Gnostics went on to argue that on that basis God himself cannot touch matter and therefore did not create the world. What he did was to put out a series of emanations. Each of these emanations was further from him, until at last there was one so distant from him that it could touch matter. That emanation was the creator of the world.
By itself that idea is bad enough, but it was made worse by an addition. The Gnostics held that each emanation knew less and less about God, until there was a stage when the emanations were not only ignorant of God but actually hostile to him. So they finally came to the conclusion that the creator god was not only different from the real God, but was also quite ignorant of and actively hostile to him. Cerinthus, one of the leaders of the Gnostics, said that “the world was created, not by God, but by a certain power far separate from him, and far distant from that Power who is over the universe, and ignorant of the God who is over all.”