'Two cities, then, have been created by two loves...'

... For just as it is not within our power to live in this flesh without the help of food, yet it is within our power not to live in it at all (as in the case of those who slay themselves), so it was not within man’s power, even in Paradise, to live well without God’s help, yet it was within his power to live ill; but then his blessedness would not endure and a most just punishment would ensue. Therefore, since God was not ignorant of the fact that man would fall, why should He not have allowed him to be tempted by the malice of the jealous angel? God was, indeed, entirely certain that the man would be vanquished; but He foresaw nonetheless that, with the help of His grace, this same devil would himself be vanquished by man’s Seed, to the greater glory of the saints. Thus it came about that no future event was hidden from God, and yet He did not, by His foreknowledge, compel anyone to sin. By the experience which followed from that sin, however, he demonstrated to all rational creatures, angels and humans alike, how great is the difference between each creature’s presumption and God’s protection. Who would dare to believe or say that it is not within God’s power to ensure that neither angel nor man should fall? Yet God preferred not to remove the choice of whether to sin or not from their power; and, in this way, He showed how great is the power of their pride for evil, and of His grace for good. Two cities, then, have been created by two loves: that is, the earthly by love of self extending even to contempt of God, and the heavenly by love of God extending to contempt of self. The one, therefore, glories in itself, the other in the Lord; the one seeks glory from men, the other finds its highest glory in God, the Witness of our conscience. The one lifts up its head in its own glory; the other says to its God, ‘Thou art my glory, and the lifter up of mine head.’ In the Earthly City, princes are as much mastered by the lust for mastery as the nations which they subdue are by them; in the Heavenly, all serve one another in charity, rulers by their counsel and subjects by their obedience. The one city loves its own strength as displayed in its mighty men; the other says to its God, ‘I will love Thee, O Lord, my strength.’ Thus, in the Earthly City, its wise men, who live according to man, have pursued the goods of the body or of their own mind, or both. Some of them who were able to know God ‘glorified Him not as God, neither were thankful; but became vain in their imagination, and their foolish heart was darkened. Professing themselves to be wise’ (that is, exalting themselves in their wisdom, under the dominion of pride), ‘they became fools, and changed the glory of the incorruptible God into an image made like to corruptible man, and to birds, and four footed beasts, and creeping things’ (for in adoring images of this kind they were either the leaders of the people or their followers); ‘and they worshipped and served the creature more than the Creator, Who is blessed forever’. In the Heavenly City, however, man has no wisdom beyond the piety which rightly worships the true God, and which looks for its reward in the fellowship not only of holy men, but of angels also, ‘that God may be all in all’. 

De Civitate Dei XIV cap 27 ad libri finem in the translation of ... I cannot recall his name at the moment R.W. Dyson, published at the Cambridge University Press