Justin Martyr, Second Apology 6

That is why God still refrains from bringing the confusion and dissolution of the entire world, so that the evil angels, demons, and human beings may not cease to exist, for the sake of the seed of the Christians, which He knows by nature is the cause. (Genesis 6–9) If this were not so, it would not be possible for you to go on doing these things and being energized by the evil demons; instead, the fire of judgment would have descended and separated everything completely, just as the flood once left no one alive except the one man with his family — called Noah by us and Deucalion by you — from whom so many have since been born, some evil and some good. We say the final conflagration will come in this way, but not as the Stoics teach, according to a theory of all things changing into one another, which is utterly shameful. Nor do we say that human beings act or suffer according to fate; rather, each person, by their own choice, either does what is right or sins. And because of the activity of evil demons, the good — people such as Socrates and those like him — are persecuted and put in chains, while men like Sardanapalus and Epicurus and their kind seem to flourish in abundance and glory. The Stoics, failing to understand this, declared that all things happen by fate and necessity. But because God made the very origin of both angels and humans self-determining, it is just that they will receive punishment in eternal fire for whatever they do wrong. For the nature of every created thing is to be capable of both vice and virtue; nothing in them would be praiseworthy if they did not have the power to turn toward either. This is shown by the people everywhere who have legislated and philosophized according to right reason, commanding certain things to be done and others to be avoided. Even the Stoic philosophers, in their ethical treatises, strongly honor the same virtues, yet their own treatises on first principles and incorporeal things undermine them. For either they will claim that what happens to human beings comes about by fate, or they will deny that there is any God other than one that is constantly changing, being altered, and dissolving into the same elements — and so they will appear to have grasped only perishable things, while God Himself, through both the parts and the whole, becomes the author of all evil or does not exist at all, and there is neither evil nor virtue — which is contrary to all sober thought, reason, and mind.