What is a Christian? In the Letter to Diognetus, which dates back to the 2nd Century A.D., an anonymous writer describes a strange people who are in the world but not of the world.
Christians are not differentiated from other people by country, language, or customes; you see, they do not live in cities of their own, or speak some strange dialect. . . . They live in both Greek and foreign cities, wherever chance has put them. They follow local customs in clothing, food, and the other aspects of life. But at the same time, they demonstrate to us the unusual form of their own citizenship.
They live in their own native lands, but as aliens. . . . Every foreign country is to them as their native country, and every native land as a foreign country.
They marry and have children just like everyone else, but they do not kill unwanted babies. They offer a shared table, but not a shared bed. They are passing their days on earth, but are citizens of heaven. They obey the appointed laws and go beyond the laws in their own lives.
They love everyone, but are respected by all. They are put to death and gain life. They are poor and yet make many rich. They are dishonored and yet gain glory through dishonor. Their names are blackened, and yet they are cleared. They are mocked and bless in return. They are treated outrageously and behave respectfully to others.
When they do good, they are punished as evildoers; when punished, they rejoice as if being given new life. They are attacked by Jews as aliens and are persecuted by Greeks; yet those who hate them cannot give any reason for their hostility.