There are fundamental questions that some want to be answered. Different approaches are taken to the same ends, be it Christianity, Buddhism, Yogas, Quantom-Physics, Psychology, Western Philosophy, etc. Where it gets dangerous is when one makes absolute statements. If I am in New York, and I wish to go to Los Angeles, I can go by many routes and methods, each having its own risks, detriments, and boons. Or I might choose not to take the route at all, satisfied with my home.
When dealing with "Why are we here? What happens to us when we die? Is there a god?" type questions, are a bit different. The traveller in NY suddenly is not even certain of proof of LA's existance. And though a few folks are ready and willing to say they know a friend of a friend who'se been there and shown the only foolproof way of making the journey, the potential traveller may not know for certain. He may have already been conned down dead-ends before. He may not want to wind up on a plane with empty fueltanks. To a certain degree you must look inside.
You said a drop of water can not encompass the sea, but I would add that only a drop can experience the sea. The drop in fact, is the sea. What first seems macro becomes micro, and yet the pattern remains. It becomes a pointless matter trying to distinguish sunlight from the sun. The Non-Dual viewpoint rips away at the curtain of this concept of "This" and "That", leaving only "That." In a sense, the universe itself, and whatever particules, minds, egos, and forces it is made of, is God itself. That makes you and everything else divine. Getting to know yourself, then becomes the most "religious" of tasks. Far more difficult then dreaming of some angry invisible man in the sky.
-Gita