Gnosticism

Gnosticism was a sect of Christianity banned by the Church as heresy. Hence, its beliefs varied across different groups, but it generally believes that Jesus was trying to bring knowledge to mankind, that (at least some) humans have divine souls trapped in the evil physical world by a demon, and those humans need to escape to the divine realm.

Gnosticism believes the God of the Old Testament was an evil demon called Yaldabaoth (the demiurge) who sought to imprison the goddess Sophia (knowledge) in the physical world (its evil creation). The serpent who guided Adam and Eve to the apple in the Garden of Eden was the good guy.

The divine realm is typically conceived as multiple layers of ideals emanating from the original ideal. (Compare Hegel's conception of dialectics and the Spirit.) Each layer brings more imperfections, until you get "archons" (angels), including Yaldabaoth, who was able to make the evil physical world.

Many historical Gnostics were merchants, hence the idealism.