If God is the Creator of all things and evil is a thing, then God is the Creator of evil and He is to be blamed for its existence. No, evil is not a thing but a wrong choice, or the damage done by a wrong choice. Evil is no more a positive thing than blindness is, but it is just as real.
Peter KreeftSocrates: So even our walks are dangerous here. But you seem to have avoided the most dangerous thing of all. Bertha: What's that? Socrates: Philosophy. Bertha: Oh, we have philosophers here. Socrates: Where are they? Bertha: In the philosophy department. Socrates: Philosophy is not department. Bertha: Well, we have philosophers. Socrates: Are they dangerous? Bertha: Of course not. Socrates: Then they are not true philosophers.
Peter Kreeft