I got into a discussion with a coworker about 2 months ago where she was talking about how Satan is the reason for evil in the world and tat God was all good. I said she was wrong and she asked me where evil comes from. I told her that evil comes from her god... she about flipped out and demanded to know where I came up with that. So I referred her to that same verse in Isaiah. She never brought up the bible around me again.
That's classic! Another way to approach the topic, knowing nothing of specific verses, is - if god created everything, he created satan, since satan is the embodiment of evil, god created evil. A simple proof that most Christians will desperately try to avoid thinking about.