54 Can, then, anything be made, some one will say, without God's will? We must consider carefully, and examine with no little pains, test, while we think that we are honouring God by such a question, we fall into the opposite sin, doing despite to His supreme majesty. In what way, on what ground? Because, if all things are brought about by His will, and nothing in the world can either succeed or fail contrary to His pleasure, it follows of necessity that it should be understood that all evils, too, arise by His will.
But if, on the contrary, we chose to say that He is privy to and produces no evil, not referring to Him the causes of very wicked deeds, the worst things will begin to seem to be done either against His will, or, a monstrous thing to say, while He knows it not, but is ignorant and unaware of them. But, again, if we choose to say that there are no evils, as we find some have believed and held, all races will cry out against us and all nations together, showing us their sufferings, and the various kinds of dangers with which the human race is every moment distressed and afflicted.
Then they will ask of us, Why, if there are no evils, do you refrain from certain deeds and actions? Why do you not do all that eager lust has required or demanded? Why, finally, do you establish punishments by terrible laws for the guilty? For what more monstrous act of folly can be found than to assert that there are no evils, and at the same time to kill and condemn the erring as though they were evil?
Source: Against the Heathen (New Advent)