Respiration and spirit share a common root. This reflects a fundamental misunderstanding in history, language, and religion. The truth is not so much that spirit and breath are similar or somehow linked in nature, but rather that the reference is the linguistic remnant of a logical fallacy in which the cognitive tendency toward reification resulted in the attribution of substance to a property.
Bodies breathe, but in the heavens there is only air.
There can, however, be insight even in misapprehension. Respiration is evidence not of soul, Geist, but the deep physical and material connection between all living things. I breathe the breath of your lungs, and the mine-ness of my breath is a contingent matter of relation and proximity. Our spirits mingle, and each breath is a repetition. In and out. Again and again. Between every breath there is a little death. A rehearsal, if you will, and a resurrection.