Reddit mentions of The Desert a City: An Introduction to the Study of Egyptian and Palestian Monasticism Under the Christian Empire

Before Christianity was legalized, it was easy to categorize Christians as an underground who practiced countercultural sexual and social ethics, practiced fasting, austerity, simplicity, pacifism, and radical hospitality and sharing - especially the refugee communities outside the cities.

After Christianity was legalized, the refugees returned to the cities; within a generation they realized what they considered normal Christian life wasn't what the new, prosperous, patriotic Christians considered normal. So the refugees and their followers returned to the deserts (classic work: The Desert, A City)

Ever since then, Christianity has existed in two streams: Regular folks living in the world, owning property, marrying and pursuing professions, and working out their salvation within a society governed by a state's laws; and those communities out on the margins, where community, austerity, pacifism and rejection of property are practiced - and the State is pretty much irrelevant. If we let the "desert communities" of monasticism influence us, then it gives us as individuals the freedom to decide just how much loyalty we're going to give the State, and what our relationship to secular authority will look like.