32 But all these things, they say, are the fictions of poets, and games arranged for pleasure. It is not credible, indeed, that men by no means thoughtless, who sought to trace out the character of the remotest antiquity, either did not insert in their poems the fables which survived in men's minds and common conversation; or that they would have assumed to themselves so great licence as to foolishly feign what was almost sheer madness, and might give them reason to be afraid of the gods, and bring them into danger with men.
But let us grant that the poets are, as you say, the inventors and authors of tales so disgraceful; you are not, however, even thus free from the guilt of dishonouring the gods, who either are remiss in punishing such offenses, or have not, by passing laws, and by severity of punishments, opposed such indiscretion, and determined that no man should henceforth say that which tended to the dishonour, or was unworthy of the glory of the gods. For whoever allows the wrongdoer to sin, strengthens his audacity; and it is more insulting to brand and mark any one with false accusations, than to bring forward and upbraid their real offenses.
For to be called what you are, and what you feel yourself to be, is less offensive, because your resentment is checked by the evidence supplied against you on privately reviewing your life; but that wounds very keenly which brands the innocent, and defames a man's honourable name and reputation.
Source: Against the Heathen (New Advent)