Down" is used many different ways, and its spiritual meaning in the Bible is highly dependent on context. Phrases like "bowing down," "lying down" and "falling down" are defined primarily by "bowing," "lying" and "falling"; there is also a great difference between a person descending, the Lord sending fire from heaven and someone handling an object, to offer a few examples. In a very general sense, though, "down" indicates a lowering from more internal spiritual states to more external ones. That's why the journey is described as going "down" to Egypt from Canaan, and people from all quarters go "up" to Jerusalem. It's also why the Lord comes "down" to us, which generally indicates a state of judgment.

If you think about sitting, it seems fair to say that where you're sitting is more important than that you're sitting. Sitting in a movie theater, sitting in a classroom, sitting in the driver's seat of a car, sitting in the defendant's seat at a trial, sitting at the family dinner table -- those are very, very different things. But even so, the fact that you're sitting in those places is important -- it means you are part of what's going on, you're staying in place. This is similar to "sitting" in the Bible. Sitting on a throne indicates judgment; sitting in a tent door indicates holiness. The context is crucial. But in all cases "sitting" indicates a sense of permanence, belonging, and full participation in the spiritual state illustrated through the context.