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Valerian's first religious edict singled out Christianity as a particularly self-interested and subversive foreign cult, outlawed its assemblies and urged Christians to sacrifice to Rome's traditional gods. His second edict acknowledged a Christian threat to the Imperial system – not yet at its heart but close to it, among Rome’s equites and Senators. Christian apologists interpreted his disgraceful capture and death as divine judgement. The next forty years were peaceful; the Christian church grew stronger and its literature and theology gained a higher social and intellectual profile, due in part to its own search for political toleration and theological coherence. Origen discussed theological issues with traditionalist elites in a common Neoplatonist frame of reference – he had written to Decius' predecessor Philip the Arab in similar vein – and Hippolytus recognised a “pagan” basis in Christian heresies. The Christian churches were disunited; Paul of Samosata, Bishop of Antioch was deposed by a synod of 268 for "dogmatic reasons – his doctrine on the human nature of Christ was rejected – and for his lifestyle, which reminded his brethren of the habits of the administrative elite". The reasons for his deposition were widely circulated among the churches. Meanwhile, Aurelian (270-75) appealed for harmony among his soldiers (concordia militum), stabilised the Empire and its borders and successfully established an official, Hellenic form of unitary cult to the Palmyrene Sol Invictus in Rome's Campus Martius.

What did  Valerian call the Christian religion?
subversive foreign cult