Some residue remaining

Where in all this is evil to be found? How did it insinuate itself? What is its root, what its seed? Or does it not exist? Then why do we fear and shun the non-existent? Even if it offers a phantom threat, the threat itself is an evil, by which the untrheatened heart is put on alert and put on the rack - the falser its terror, the more obvious is the evil of fearing what is not there to be feared. Do we fear a real evil, or is the fearing itself the evil? How can this occur, when God created all these good things out of his own goodness? Even if the highest goodness made lower goods, everything involved is good, the maker and the things made. Then where is there room for evil? Is the matter from which he made things somehow evil, to which he gave form and rank but left some residue of it unchanged into good? How can this be? Was he so weak, he the all-powerful, that he had to leave some trace of evil behind when he shaped and transformed matter? If that were the case, why would he want to make things at all, intead of using all his power to prevent them?

Augustine, Confessions 7.7 (140-141 in Wills)