To speak in general terms, we may say that the Christian is to the world what the soul is to the body. As the soul is present in every part of the body, while remaining distinct from it, so Christians are found in all the cities of the world, but cannot be identified with the world. As the visible body contains the invisible soul, so Christians are seen living in the world, but their religious life remains unseen. The body hates the soul and wars against it, not because of any injury the soul has done it, but because of the restriction the soul places on its pleasures. Similarly, the world hates the Christians, not because they have done it any wrong, but because they are opposed to its enjoyments. (from the Letter to Diognetus (from Mathetes) 2nd Century AD)
For we offer prayer for the safety of our princes to the eternal, the true, the living God, whose favour, beyond all others, they must themselves desire. They know from whom they have obtained their power; they know, as they are men, from whom they have received life itself; they are convinced that He is God alone, on whose power alone they are entirely dependent, to whom they are second, after whom they occupy the highest places… For he himself is His to whom heaven and every creature appertains. He gets his sceptre where he first got his humanity; his power where he got the breath of life. …Without ceasing, for all our emperors we offer prayer. We pray for life prolonged; for security to the empire; for protection to the imperial house; for brave armies, a faithful senate, a virtuous people, the world at rest, whatever, as man or Cæsar, an emperor would wish. These things I cannot ask from any but the God from whom I know I shall obtain them, both because He alone bestows them and because I have claims upon Him for their gift, as being a servant of His, rendering homage to Him alone, persecuted for His doctrine, offering to Him, at His own requirement, that costly and noble sacrifice of prayer… (Tertullian: Apologeticus pro Christianis, XXX, AD 197)
There is also another and a greater necessity for our offering prayer in behalf of the emperors, nay, for the complete stability of the empire, and for Roman interests in general. For we know that a mighty shock impending over the whole earth—in fact, the very end of all things threatening dreadful woes—is only retarded by the continued existence of the Roman empire. We have no desire, then, to be overtaken by these dire events; and in praying that their coming may be delayed, we are lending our aid to Rome’s duration. (Tertullian: Apologeticus pro Christianis, XXXII, AD 197)
Praised be Jesus Christ, now and forever.