We have now seen that there are three kinds of theology, called by the Greeks mythical, physical, and political, and which may be called in Latin fabulous, natural, and civil. And we have seen that there is no hope of eternal life to be derived either from the fabulous system, which even the worshipers of the many false gods openly criticize, or from the civil, which includes the fabulous as one of its parts and which is like, or even worse than, the part. If any reader feels that enough has not been said on these points in the present Book, let him read what has been written above, particularly in Book IV on God as the Giver of happiness.
For, to whom—if not to Felicity alone—should men who want eternal life dedicate themselves, if, indeed, Felicity were divine. But, since happiness is not a goddess, but a gift of God, to what God save the Giver of happiness should we consecrate ourselves? For, we love with religious charity that eternal life where there is a true and complete beatitude. I think, from what I have said so far, that no one can imagine that the Giver of happiness is any of those gods who are worshiped with such indecent rites, and are more indecently angry when they are not so worshiped, and who thus show themselves to be nothing but unclean spirits.
Further, how could anyone give us eternal life who cannot even make us happy? And, by eternal life I mean a life where there is happiness without end. For, if a soul lives in eternal pains, in which those unclean spirits are to be punished, that is eternal death rather than eternal life. There can be no greater or worse death than where death itself never dies. Since it is the nature of the soul that it cannot be without some sort of life, having been created immortal, it is the depth of death for it to be alienated from the life of God in an eternity of pain.
Of eternal life, that is to say, of life that is happy without end, only He is the Giver who gives genuine beatitude. This is something which, as has been shown, those gods who are worshiped in accordance with the theology of the state cannot give. And, therefore, it is useless to worship them with a view to temporal and terrestrial benefits (as I have shown in the previous five Books) and still more useless to worship them with a view to eternal life which begins after death (as I have shown in this Book—with supporting arguments from the others). However, old habits have deep roots, and there may be some who feel I have said too little to convince them to disavow and give up this way of worship. I must commend to their attention a subsequent Book which, with the help of God, I hope to join to this one.
Augustine of Hippo, The City of God, Books I–VII