[VemyhemiHef]

Why do we need to be in another level of consciousness to seperate from our bodies? Why can't we just do it at will?

Survival. Because it requires a shift of your awareness, your sense of self into another environment. If we did it all the time (that is, be consciously immersed in a nonphysical environment) we would probably fall off a cliff or get run over by a car- because most people can't completely have their attention in two places in one time, and the physical needs attention- it's too easy to get killed or die in some way.
Think of it like this- you are already in the astral, in the mental, etc. But your attention is in the physical through your body. Because you have to walk, talk and function in the physical. If you don't, you won't survive. Your attention is here while awake. When you go to sleep, your body and mind are in a controlled environment (your room, on a bed, protected). Then you can shift your attention to the nonphysical.

Why is the air so damn grainy after I am out? Because you are sensing with your energy body, not with your eyes. You don't have eyes, you are an energy field that senses by interacting with your environment, like radar. So what you 'see' is the information gathered by your energy body translated into images by your brain.

What is all that stuff, is it energy? Yes, in fact, everything is energy, even the physical.

Is that how the 4th dimension looks? The fourth dimension is time. Science fiction ruined the idea of dimensions for us. The physical dimensions are, height, width, depth, and time.
There are supposed to be other dimensions that are unspecified because we can't perceive them, (up to eleven, IIRC) because they are too small, according to modern physics. (Stephen Hawkings) in string theory. It is possible that when we become nonphysical we are able to perceive such dimensions, but no one really knows what the truth is.

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