In plain words
So there is in man one divine power that breathes life into all the karaṇas and makes each of them carry out its own duty.
This very power we ordinarily call prāṇa. But where does this prāṇa come from, and where does it go? Who sends it? This is the very question the Kenopaniṣad asks. It went on to enquire whether this divine power that makes us speak, makes us hear, makes us feel, makes us think and gives us delight belongs to prāṇa, or whether there is some other power, master even over prāṇa. The sun shines. The moon shines only by the support of the sun's light. The moon's light falls on the earth. Then the earth too shines. But by what does this earth shine? Just by the light of the moon. By what does the moon shine? Just by the light of the sun. But by what does the sun shine? That itself is the divine power. The hydrogen and helium in it: from what power did they come forth? This the Upaniṣads called the principle of Brahman. By the light of this Brahman alone the whole world, all of it, shines; Brahman alone makes things shine, and there is nothing in the world that makes Brahman shine; the light of this Brahman reaches the eyes and the eyes are able to see; the eyes can see, but the eyes cannot see Brahman. Taking its support from this light, the mind develops its saṅkalpas, but the mind cannot describe this Brahman. That is why the Upaniṣads, with Yato vācā nivartante aprāpya manasā sahaḥ, have shown that a divinity beyond both mind and speech lies hidden in man. So, though such a divine and glorious power lies hidden in man, man cannot recognise it. What is the reason? In his life man strives to develop his outward vision, but he does not reach out in the least to make the effort and experience the inner vision.