"Jesus himself, and most of the message of the Gospels, is a message of service to the poor, a critique of the rich and the powerful, and a pacifist doctrine. And it remained that way, that's what Christianity was up... until Constantine. :Constantine shifted it so the cross, which was the symbol of persecution of somebody working for the poor, was put on the shield of the Roman Empire. It became the symbol for violence and oppression, and that's pretty much what the church has been until the present."

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I think it's important to realise that what happens in Neo-Platonism beginning with Plotinus and Porphyry and then going on for the next several centuries, is a real kind of contest for the ideas and convictions of the intelligentsia of the later Roman Empire. So that you have Christians slowly converting more and more powerful people until of course actually Constantine and then other emperors after him, become Christian, and the empire becomes a Christian empire rather than Pagan empire.

— Peter Adamson