Nicene and Post-Nicene Fathers, Vol. II:
City of God: Chapter 36

Chapter 36.—What Subjects are to Be Handled in the Following Discourse.

But I have still some things to say in confutation of those who refer the disasters of the Roman republic to our religion, because it p. 22 prohibits the offering of sacrifices to the gods.  For this end I must recount all, or as many as may seem sufficient, of the disasters which befell that city and its subject provinces, before these sacrifices were prohibited; for all these disasters they would doubtless have attributed to us, if at that time our religion had shed its light upon them, and had prohibited their sacrifices.  I must then go on to show what social well-being the true God, in whose hand are all kingdoms, vouchsafed to grant to them that their empire might increase.  I must show why He did so, and how their false gods, instead of at all aiding them, greatly injured them by guile and deceit.  And, lastly, I must meet those who, when on this point convinced and confuted by irrefragable proofs, endeavor to maintain that they worship the gods, not hoping for the present advantages of this life, but for those which are to be enjoyed after death.  And this, if I am not mistaken, will be the most difficult part of my task, and will be worthy of the loftiest argument; for we must then enter the lists with the philosophers, not the mere common herd of philosophers, but the most renowned, who in many points agree with ourselves, as regarding the immortality of the soul, and that the true God created the world, and by His providence rules all He has created.  But as they differ from us on other points, we must not shrink from the task of exposing their errors, that, having refuted the gainsaying of the wicked with such ability as God may vouchsafe, we may assert the city of God, and true piety, and the worship of God, to which alone the promise of true and everlasting felicity is attached.  Here, then, let us conclude, that we may enter on these subjects in a fresh book.