The Republic by Plato Part 2 Page 76

right, and they were the better for being punished; but that those who are punished are miserable, and that God is the author of their misery — the poet is not to be permitted to say; though he may say that the wicked are miserable because they require to be punished, and are benefited by receiving punishment from God; but that God being good is the author of evil to any one is to be strenuously denied, and not to be said or sung or heard in verse or prose by any one whether old or young in any well-ordered commonwealth.

Such a fiction is suicidal, ruinous, impious.

I agree with you, he replied, and am ready to give my assent to the law.

Let this then be one of our rules and principles concerning the gods, to which our poets and reciters will be expected to conform, —