2nd Hermetic Principle: Principal of Corraspondence. (As above so below.)
The things that we do here in this earth can affect us spiritually and visa versa. When we create a circle we are bridgeing the gap between these two worlds makeing within it a sacred space from which magick can be done. When we use a wand to work with Air energy it is not the tool that makes it happen it is the bridge between our world of the physical and the world or realm of energy. When we astral project we are leaving this physical world behind for a time and entering the spirtual world to see things and experience things from that perspective. Any real healer knows that real healing must be preformed on the spiritual body of a person as well as the physical body hence the reason why Riki works.
I do not believe that this is a karmic law. It does not mean at least not to me that what I do will return to me so many fold. If it did I personally think the world would have been destroyed a long time ago.
Like wise as to the above energy has two aspects. That which can be felt spirtually and that which can be felt physically or Chakra or Ki energy. As above is first which I take to mean that we start low here in this earth and we seek to attain a higher self thus meditation and other building blocks of magical practice. This will naturally lead to physical energy and the honeing of skills and abilites that border on the natural aspects of ourselves. This though is just my theory and opinion.