Great job giving a real creative background to the cult. It reads like a well thought out piece of fantasy fiction where any questions the players may have can be answered to a satisfying degree.
I was delighted with lots of little remarks and flavourful additions in the text that show the signs of an experienced designer. Reading the text gives me plenty for the players to interact with.
In closing I also want to remark the beautiful use of art to break up the text. Nothing ever felt long-winded or overly dense.