Chandogya Upanishad, one of the oldest Upanishad has been written during the Vedic Brahmana period. Chandogya Upanishad is associated with Sama Veda. It is ranked ninth in the Muktika canon of hundred and eight Upanishads. Chandogya Upanishad is the part of Chandogya Brahaman that contains ten chapters. The 1st Khanda of Part Five of Chandogya Upanishad describes about the supremacy of the Prana. One who is aware of the eldest and greatest verily becomes the eldest and greatest i.e. jesta-srestha. The prana is the oldest and greatest. One who is aware of what is most excellent i.e. vasishtha verily becomes the most excellent among his kinsmen. The organ of speech is the most excellent. One who is aware of the attributes of firmness (pratishtha) becomes firmly placed in this and the next world. The vision i.e. the eye is the symbol of firmness. He who is aware of Sarapad i.e. fortune, obtains that is desirable in this or the other world. The ear is verily the Sarapad. He who knows about the receptacle i.e. Ayatana becomes the receptacle of his people. The mind is the receptacle.
The pranas that is the sense organs now disputed among themselves as to who was the best among them. They went to Prajapati and asked him for a solution. Prajapati told them that the best among them was the one by whose departure this body is considered to suffer most. To prove themselves all the organs began to depart from the body one after the other. Firstly the organ of speech departed. It then returned after a year. This caused no problem as the body though remained dumb but was able to survive with the help of other organs. Similar was the case with the eye. The body lived as blind men but it survived easily with the help of the vital breath. Next the ear, then the mind and then the organ of generation went away each for a year. However, the body easily survived with the help of the vital breath and other organs. Finally when the vital breath was about to leave it uprooted the organs from their places. The other organs immediately stopped it as it was impossible to live without it. Thus, the vital breath or the Prana is the most important of all the organs.
