There is a blurb from the Midgard Wiki about the Derwisch (aka Dervish). That article does not contain much but you can get more by delving deeper into the articles.
The Dervish is a strictly believing Dhulam. Alone or in small faith groups he studied in the Desert Storm eschar for perfection. For the most part, the dervishes belong to the order of the dancing dervishes . The caliph of Mokattam used dervishes as a battalion; They fight two- handedly with the Nimcha sword. A typical type of their sorcery are the magic dances . (Link)
Derwisch are a group of holy warriors somewhat resembling Muslim warriors during the middle ages. Faith is a huge part of their lives and most of their decisions revolve around the impact their decisions might have on their souls in the afterlife.
Derwisch are strictly believing Dhulam which are believers of Din Dhulahi (aka The Duality). They believe in the duality of their gods Ormut (Light) and Alaman (Darkness).
In order that they may not depart from the right path, Ormut has given each of them two guardian angels, one protects the body, the other the soul. Alaman, on the other hand, has given them a spirit to lead them into temptation and thus to Alaman. After the death of a believer, the result of this lifelong struggle between the guardians and the spirit decides about the life after death. Either the soul lives to the end of the world in the light heaven of Ormut, or it must serve the Iblisi Alamans (Creatures that come from Alaman's Blood that brought sickness and death to creation). (Link)
- Dhulahim must pay tribute to Ormut at sunrise and sunset and at noon.
- Dhulahim must never extinguish a fire except in emergencies.
- Dhulahim are not
allowed to use fire for low purposes (for example, to burn trash).
- Dhulahim must honor the dead and not rob them (unbelievers are
excluded in many places).
- Dhulahim must light a memorial fire in the
night of the Aid el-Uled ed-Dhar and honor the dead.
- Dhulahim must
observe the fasting time before the new moon of the light bird.
- Dhulahim shall not shed blood in the noon, except sacrifices and war.
- Dhulahim must never stand so that their own shadow falls upon the
heart of another Dhulam.
- Dhulahim must not smoke.
The original translation of the second prohibition was "Dhulahim must never extinguish a fire except a fire." but it used different words for either fire, the first just being Feuer (fire) but the second one Brand could be read as Blaze so I think the intent here is to say "Don't put out fires unless it's out of control"