Most people during a particular period in a particular area in my world were Nostyls:
What does the faith say about the nature of reality?
The faith basically says that the material world is the domain of multiple Gods who are evil, but the human soul itself is separate from those evil carnal features. There's a focus on the idea that external reality is illusory and it's better to look towards the soul to attain knowledge.
How do worshippers experience the divine?
Principally through language. The religions founder basically invented his own language to write the Holy Book, and it's believed that you must use this language to talk to basically the communion of saints (aka the souls of true believers.)
What are the philosophical tenets of your religion?
One of the features of the religious text is that all power is ultimately a curse that will end in failure and destruction. The religion teaches the best approach to life is to avoid carnal desires and to put morality and the soul above all material things. One feature of this is that it does result in a somewhat lax approach to killing, because physical life isn't seen as being anything like as important as the purity of a community through the purity of the souls. So a lot of strict punishments in this society.
How is the faith structured?
This is a subject of much debate. The religion is quite consistently episcopalian with a ruler at the top, but there have been plenty of wars over how this leader should be chosen.
Does your religion hold bearing over legal systems and law (IE Shariah Law)?
Yes. Basically that's all there is to it. The religion is a bit like a cross between Catholicism and early Islam with the founder of a religion also founding a powerful empire Muhammad style.
Is there a sacred text/mythic narrative from which believers can seek guidance?
Basically, yes. The text describes how there was once a perfect creator God who established subordinate quasi-physical Gods to rule over all the different parts of the earth. However, the physical Gods attacked the creator God and tore him apart. As he died his blood fell on the earth and created human beings. But also his heart fell down to earth. His heart served as a Holy Spirit of sort, and the main holy text tells the story of God's heart entering the hearts of all sorts of people and the way it manifests itself. This culminates in the heart entering the body of the religion's founder, who officially establishes the religion. There's also a subsequent text about the religion's founder killing the physical Gods. There's a big debate over whether this means that the carnal Gods are dead or if it just means that the founder of the religion slayed his own personal demons.
What is the ultimate goal of the faithful?
The ultimate goal is to be like God. Basically reaching into the soul and finding the actual presence of the first creator God within you. The belief is that if enough people find their own God then God will actually appear on earth in the form of a man and raise the souls of all those who have achieved a sufficient degree of connection to the true God.
Then... A guy came down to earth who did claim to be the True God. He taught a message of loving others and serving your enemies. Eventually he was crucified, but rose from the dead three days later. He promised that he would return again and a lot of people believe that is true.