The world has entered a new era as traditional pagan religions decline in favor of newer ones. In Persia, the new religion of Christianity has been given institutional support. The Apostolic Church, led by the Patriarch of Ctesiphon, has adopted its institutional structure to that of the Sassanid Empire’s administrative divisions. Beneath the Patriarch, the Church’s bishops each have jurisdiction over a shahr[1] roughly corresponding to the Empire’s satrapies, which could be itself subdivided into parishes. The Apostolic Biblical Canon ins similar to the OTL Catholic or Orthodox Canons, but with a few major differences; the Acts of the Apostles are significantly different, and the Epistle to the Persians written by the Church’s third Patriarch, Saint Kaveh, is included, as is Ezra-Nehemiah. The Bible is always written in Aramaic, which is treated as a holy language[2]. The Emerging Nazarene Church uses the same Canon that the Apostolics do.
While the Apostolic Church rises to dominance in the Persian east, in the Roman west, the various Gnostic churches have become the most prominent sect. In addition to the four canonical gospels, the books of Judas and sometimes Thomas are also used. The Old Testament is also significantly altered, portraying the God of the Old Testament as a malevolent being inherently inferior to that of the New. The Palmyrene Emperor Odaenathus has allowed Gnostics to freely practice their religion so as to weaken Apostolic presence in his empire.
Odaenathus has sought to reform the traditional Greco-Roman religion to better compete with Christianity. In the emerging Palmyrene state religion, the primordial deity Aion, or the Monad, was the first thing to exist. From Aion emanated Mithras, the Celestial Demiurge, and his wife Isis. Mithras slew a primordial bull to create the world. Odaenathus and his wife Zenobia were worshipped as the earthly emanations of Mithras and Isis, setting the precedent for future emperors to proclaim themselves as living gods. In addition to Mithras and Isis, the old Dodekatheon are also worshipped, as well as the originally Syrian gods Atargatis and Hadad, the Phrygian Cybele/Magna Mater, and the Greco-Egyptian god Serapis. In addition to the gods worshipped as part of the state religion, various local deities were also worshipped, often as emanations of the official pantheon.
Traditionally, the Greco-Roman aristocracy would pursue one or both of two pursuits; the military and politics. However, the Palmyrene Empire was an absolute monarchy run by an all-powerful god-emperor, thus strangling the aristocracy out of their traditional senatorial careers, and the military consisted largely of conscripted barbarians who were commanded by Semitic Palmyrenes, thus strangling them out of any military career. The end result of this was a class of wealthy landowners who had nothing to do but think[3]. This ended up benefiting Odaenathus’ religious experiment, as it led to a flourishing of Neoplatonic philosophy. The new philosopher class would develop their own ideas that would effect Palmyrene society.
The Palmyrenes would adopt Plato’s Republic as their basis for an ideal society, and as a result, Palmyra would become about as socially stratified as you would expect. A sort of caste system would develop, with the emerging landowner-philosopher class on top, then the temple priests, then the legionaries, then the free citizens, and finally the slaves. It was the last who would make up the majority of the population, and the Neoplatonic renaissance would lead to a flourishing of slavery in Palmyra, backed up by the writings of Plato and Aristotle. A distinct set of rules developed surrounding social interactions between different castes. The Emperor was viewed as being outside of the emerging caste system due to being seen as a semi-divine being. Among many lower-caste Palmyrenes, the mere presence of the Emperor was seen as a religious experience, and custom dictated that one would avert their eyes when in his presence(although this wouldn’t develop until later).
[1]Middle Persian for “province”
[2]Think like Hebrew in Judaism or Arabic in Islam. The use of a holy language is part of the influence of the local culture. The choice of Aramaic is because it was both the lingua franca in the Middle East at the time and the language spoken by Jesus.
[3]This happened to the traditional Persian aristocracy IOTL after the Islamic conquest, leading to the Islamic Golden Age