Gods, Spirits, Angels, Overlords, Great Old Ones, ...
There are countless entities that are in some form superior to us, often on such a level we cannot even comprehend. In turn, we often don't even see them. They are bigger than galaxies and yet walk among us. Each of them has a realm. Some overlap, some are (part) merged, some are so far from another that they'll never touch. They influence each other, often in ways we don't realize. The weather, for example, doesn't work as you think it does. The wind you feel? That's another realm, or layer, passing through ours. Intense clouds one a boiling hot day? Strange coloration of the sky? Auroras? That's over layers visible in the sky. Unexplainable sounds you hear? Touch you feel when nobody's there? The same. And all of them are ruled and influenced by creatures so beyond us our heads would explode if we tried to grasp them. That's why we bow our heads and accept their might.