Barnes writes, “when Christians were executed by imperial order under Decius and Valerian, crowds still openly jeered at martyrs and their sympathizers. In the ‘Great Persecution,’ however, evidence of similar hostility is almost entirely lacking; by the last decades of the third century, the Christian church had become an established and respectable institution.”

That should have been enough to alert Diocletian and Galerius that this was going to be the last of the persecutions.

Not everyone found the church respectable, Barnes notes. Intellectuals argued, like Celsus, “that Christianity was intellectually disreputable.” Especially Porphyry who argued that “Christianity was incompatible with civilization. Christians were denounced as barbarians, as apostates from ancestral religion, as atheists who deserved punishment. Specifically, Porphyry argued that the profession of Christianity ought rightfully to be considered a capital crime. Such an argument was not an idle, theoretical, or academic exercise: Porphyry desired to encourage the imperial authorities in a policy of bloody repression.”