He who understands all and who knows all, he to whom all this glory in the world belongs, the Self, is placed in the ether, in the heavenly city of Brahman (the heart). He assumes the nature of mind, and becomes the guide of the body of the senses. He subsists in food, in close proximity to the heart. The wise who understand this, behold the Immortal which shines forth full of bliss.

In plain words: The Self knows and understands everything, and all the glory of the world is his. He lives in the space of the heart, called Brahman's city. He takes the form of the mind, guides the body and senses, and is kept alive by food near the heart. Wise people who understand this see the immortal one shining with joy.