If Jon had to be stuck in this frozen-time world for another hour, he'd rather have a little fun with it. But as it was, he couldn't move or change anything in this environment. At least, not yet.
He ran back up to his room (fortunately, he didn't close his door before he froze time) and grabbed the stone. But when he tried to pick it up, he discovered that it felt just as weighted down as the rest of this frozen-time world. Would it even work when time was frozen? There was only one way to find out.
Jon touched the stone and said "I wish I could move things and people when time is frozen."