Gnosticism is the view that the creator God is blind or evil, and that the world we inhabit is therefore a prison we must escape. It’s not just the material world which is bad. The angels or “archons” are jailers attempting to keep us there. The only way out is by making contact with the Supreme Being who is the source or parent of the Demiurge, and this happens through the process of gnosis or direct knowledge.
Aside from the rejection of traditional religion in favor of direct knowing, Crowley rejected all of that. The universe does not need to be escaped. It is not bad or evil or a prison. Some spirits are good and will help you if properly contacted and vetted.
There is a Demiurge in Thelema. It’s Tetragrammaton, the formula of the elements and the formula of the redemption of Malkuth. In other words it’s a personification both of manifest existence and the redemption of that existence. It is “blind” in the sense that the universe we inhabit obeys impersonal mathematical laws of cause and effect. And in a certain sense the human in its natural condition is also blind, pushed this way and that by forces beyond its control, deluded into thinking it’s making free choices when all the while it’s just a puppet of fate.
There is an alternative to this, but it does not require escaping this universe. Rather it requires us to identify with the universe, and in effect to take up the position of the Demiurge. This is exactly how Crowley conceives of the Sphinx or the pyramid (or pentagram), which are described by the formula of Tetragrammaton, which is also the formula of the Demiurge.
As recounted in Ithell Colquhoun’s biography of Mathers, Crowley learned from Mathers the secret that the God worshipped in Judaism and Christianity—Jehovah—was in fact Samael, the Blind God. Samael is androgynous when combined with his female counterpart, Lilith. Together they form CHIVA, Chioa. That’s more or less how Crowley came to understand the Sphinx, as the combination of Babalon and the Beast. They are joined—and the pyramid is completed—by means of the formula of the Rose Cross.
This is a step along the way to the redemption of—not escape from—the manifest universe, Malkuth. This redemption does not occur through self-sacrifice or suffering but rather through love under will or Thelemic magick. The apotheosis of this path is to witness ALL change—every event—as an expression of cosmic love, the product of the intercourse between Hadit and Nuit. This perfect love of Nuit is identical with pure will, unassuaged of purpose, delivered from the lust of result. Thus is suffering overcome, not by escaping existence, but by being able to experience it as pure joy.