A thesis statement must include the man point your essay is going to make about the Devil and Tom Walker. No one can give you a thesis statement without knowing this. If you are asking what would be a good topic to right about the Devil and Tom Walker then I cannot help you, because I am not familiar with the story .Be creative and I am sure you will come up with something. Ask yourself what intrigued you the most about the story. What was its most interesting aspect. As you see it.