The sun rises as the external Prâna, for it assists the Prâna in the eye. The deity that exists in the earth, is there in support of man's Apâna (down-breathing). The ether between (sun and earth) is the Samâna (on-breathing), the air is Vyâna (back-breathing).

In plain words: The breaths inside us match powers in nature. The sun is the outer Prana and helps our eyes see. The earth's power supports the downward breath. The space between earth and sky matches Samana, the middle breath, and the air matches Vyana, the breath that moves all through us.