Nicene and Post-Nicene Fathers, Vol. II:
City of God: Chapter 1

Chapter 1.—Whether, Since It is Evident that Deity is Not to Be Found in the Civil Theology, We are to Believe that It is to Be Found in the Select Gods.

If there is any one whom the sixth book, which I have last finished, has not persuaded that this divinity, or, so to speak, deity—for this word also our authors do not hesitate to use, in order to translate more accurately that which the Greeks call θεότης;—if there is any one, I say, whom the sixth book has not persuaded that this divinity or deity is not to be found in that theology which they call civil, and which Marcus Varro has explained in sixteen books,—that is, that the happiness of eternal life is not attainable through the worship of gods such as states have established to be worshipped, and that in such a form,—perhaps, when he has read this book, he will not have anything further to desire in order to the clearing up of this question.  For it is possible that some one may think that at least the select and chief gods, whom Varro comprised in his last book, and of whom we have not spoken sufficiently, are to be worshipped on account of the blessed life, which is none other than eternal.  In respect to which matter I do not say what Tertullian said, perhaps more wittily than truly, “If gods are selected like onions, certainly the rest are rejected as bad.” 250   I do not say this, for I see that even from among the select, some are selected for some greater and more excellent office:  as in warfare, when recruits have been elected, there are some again elected from among those for the performance of some greater military service; and in the church, when persons are elected to be overseers, certainly the rest are not rejected, since all good Christians are deservedly called elect; in the erection of a building corner-stones are elected, though the other stones, which are destined for other parts of the structure, are not rejected; grapes are elected for eating, whilst the others, which we leave for drinking, are not rejected.  There is no need of adducing many illustrations, since the thing is evident.  Wherefore the selection of certain gods from among many affords no proper reason why either he who wrote on this subject, or the worshippers of the gods, or the gods themselves, should be spurned.  We ought rather to seek to know what gods these are, and for what purpose they may appear to have been selected.

Footnotes

Tert. Apol. 13, Nec electio sine reprobatione; and Ad Nationes, ii. 9, Si dei bulbi seliguntur, qui non seliguntur, reprobi pronuntiantur.