When I was in college we used to sit around and discuss some of the deep theological issues of life. One of the questions we usually talked about was, “If God can do everything, then can he make a rock larger than he can lift?” It is a useless and unanswerable question because it pits God against himself. About the only good it did was to keep us off of the streets. That might have been a blessing. But it does introduce the subject: there are some things that even God cannot do.