Diognetus weighs in

This is another reprint of one of Pastor Leon Stier's devotions (you can find more info or subscribe here)

From the LETTER TO DIOGNETUS on the Early Christians (2nd century, A. D.)

From The Early Christians: In Their Own Words , (ch. 3, #28); Selected and Edited by Eberhard Arnold (1883-1935)

Christians cannot be distinguished from the rest of humankind by country, speech, or customs. They do not live in cities of their own; they do not speak a special language; they do not follow a peculiar manner of life. Their teaching was not invented by the ingenuity or speculation of men, nor do they advocate mere book learning, as other groups do. They live in Greek cities and they live in non-Greek cities according to the lot of each one. They conform to the customs of their country in dress, food, and the general mode of life, and yet they show a remarkable, an admittedly extraordinary structure of their own life together. They live in their own countries, but only as guests and aliens. They take part in everything as citizens and endure everything as aliens. Every foreign country is their homeland, and every homeland is a foreign country to them. They marry like everyone else, and beget children... They are in the flesh, but they do not live according to the flesh. They live on earth, but their citizenship is in heaven. They obey the established laws, but through their way of life they surpass these laws. They love all people and are persecuted by all. Nobody knows them, and yet they are condemned. They are put to death, and just through this they are brought to life. They are as poor as beggars, and yet they make many rich. They lack everything, and yet they have everything in abundance. They are dishonored, and yet have their glory in this very dishonor. They are insulted, and just in this they are vindicated. They are abused, and yet they bless. They are assaulted, and yet it is they who show respect. Doing good, they are sentenced like evildoers. When punished with death, they rejoice in the certainty of being awakened to life. Jews attack them as people of another race, and Greeks persecute them, yet those who hate them cannot give any reason to justify their hostility.... How they are thrown to the wild beasts to make them deny the Lord! How unconquerable they are! Do you not see that the more of them that are executed, the more do the others grow in number? That is clearly not the work of men. That is the power of God. That is proof of his presence.

In a word: what the soul is in the body, the Christians are in the world. As the soul is present in all the members of the body, so Christians are present in all the cities of the world. As the soul lives in the body, yet does not have its origin in the body, so the Christians live in the world yet are not of the world. Invisible, the soul is enclosed by the visible body: in the same way the Christians are known to be in the world, but their religion remains invisible. Even though the flesh suffers no wrong from the soul, it hates the soul and fights against it because it is hindered by the soul from following its lusts; so too the world, though suffering no wrong from the Christians, hates them because they oppose its lusts. The soul loves the flesh, but the flesh hates the soul; as the soul loves the members of the body, so the Christians love those who hate them. The soul is enclosed in the body, yet it holds the body together; the Christians are kept prisoners in the world, as it were, yet they are the very ones who hold the world together. Immortal, the soul lives in a mortal house; so too the Christians live in a corruptible existence as strangers and look forward to incorruptible life in heaven. When the body is poorly provided with food and drink, the soul gains strength. In the same way the number of Christians increases day by day when they are punished with death. Such is the important task God has entrusted to the Christians and they must not shirk it.