From a letter to Diognetus
The Christian in the world
Christians are indistinguishable from other men either by nationality, language or customs. They do not inhabit separate cities of their own, or speak a strange dialect, or follow some outlandish way of life. Their teaching is not based upon reveries inspired by the curiosity of men. Unlike some other people, they champion no purely human doctrine. With regard to dress, food and manner of life in general, they follow the customs of whatever city they happen to be living in, whether it is Greek or foreign.
And yet there is something extraordinary about their lives. They live in their own countries as though they were only passing through. They play their full role as citizens, but labor under all the disabilities of aliens. Any country can be their homeland, but for them their homeland, wherever it may be, is a foreign country. Like others, they marry and have children, but they do not expose them. They share their meals, but not their wives. They live in the flesh, but they are not governed by the desires of the flesh. They pass their days upon earth, but they are citizens of heaven. Obedient to the laws, they yet live on a level that transcends the law.
Christians love all men, but all men persecute them. Condemned because they are not understood, they are put to death, but raised to life again. They live in poverty, but enrich many; they are totally destitute, but possess an abundance of everything. They suffer dishonor, but that is their glory. They are defamed, but vindicated. A blessing is their answer to abuse, deference their response to insult. For the good they do they receive the punishment of malefactors, but even then they rejoice, as though receiving the gift of life. They are attacked by the Jews as aliens, they are persecuted by the Greeks, yet no one can explain the reason for this hatred.