Arguing for or against the existence of God is a traditional philosophical issue and a very good topic for a paper. Berkeley argues for the existence of God in Dialogues 2 and 3, especially 3, though parts of 2 may be useful. (With an electronic text you can just search for “God” to find the relevant passages. Leibniz discusses God in the later passages of the Monadology.
Better yet, Hume argues that we cannot know if there is a God or not in chapter 2 of the Natural Religion book. Notice that Hume’s argument is about human beings knowing whether or not there is a God (epistemology) and not about the actual existence of God (ontology). So, he’s talking about something that is just a little different.
