Christians are not distinguished from the rest of mankind by locality, speech or customs. They do not dwell in cities of their own, have a different language, or practise a strange kind of life. But while they dwell in cities, as the lot of each is cast, they following the local customs in dress and food and the other arrangements of life, the nature of their citizenship contradicts expectation. They dwell in their own countries, but as sojourners; bearing their share in all things, yet they endure hardships as strangers. Every foreign country is to them a fatherland and every fatherland foreign. They marry and have children; but do not cast them away. They share their meals, but not their wives. Finding themselves in the flesh, they do not follow its desires. Their existence is on earth, but their citizenship is in heaven. Obeying the established laws and surpass them in their own lives. They love all men, yet persecuted by them. They are ignored and condemned. They are put to death, yet they have life. They are poor, yet they make many rich. They are in want, yet they abound. They are dishonoured, yet they are glorified in their dishonour. They are reviled, and they bless; insulted, yet show respect. Doing good they are punished; being punished they rejoice. Even thought war is waged against them, those that hate them cannot tell the reason for their hostility.
What the soul is to the body, so are Christians to the world. The soul is spread throughout the many members of the body; Christians throughout the varied cities of the world. The soul has its abode in the body, and yet it is not of the body. Likewise, Christians have their abode in the world, and yet they are not of the world. The soul, though itself immortal, dwells in a mortal tabernacle; Christians sojourn amidst perishable things, while they look for the imperishability of heaven.
For this was no earthly discovery that was committed to them, nor do they preserve some human mystery entrusted to them. Truly, the all-creating invisible God planted among men him who is the Truth and the Word, which surpasses the understanding of man, fixing him firmly in their hearts – not, as one might imagine, by sending a servant, or angel, but by sending the very maker of the Universe, through whom the heavens were made – the heavens and all that is in them, the earth and the things in the earth, the sea and the things that are in the sea, the fire, air, abyss, the things in the heights, the things in the depths and all things in between. Do you think he was sent, as one might suppose, to establish a reign to inspire fear and terror? No, not at all, but in gentleness and meekness he sent him, as a king sending his son. He sent him, as a man to men; a Saviour, using persuasion, not force; summoning, not persecuting; loving, not judging. But one day he will send him in judgment, and who then shall endure his presence?
They are thrown to wild beasts so that they may deny the Lord, and yet are not overcome. The more of them that are punished, the more others abound. These do not resemble the works of a man. They are the power of God, the very proof of his presence.
[Extract from Epistle to Diognetus, circa AD 130. Based on translation by Lightfoot and Harmer, 1891, with my abbreviations and amendments for clarity.]