He who sees Him seated in the five elements, born of Tapas (fire of Brahman), born before water; who, having entered the cave of the heart, abides therein --this verily is That.
This verse indicates that He, the Great Self, is the cause of all created objects. According to the Vedas, His first manifestation was Brahma, the Personal God or Creator, born of the fire of wisdom. He existed before the evolution of the five elements-- earth, water, fire, air and ether; hence He was "born before water." He is the Self dwelling in the hearts of all creatures.
VII
He who knows Aditi, who rises with Prana (the Life Principle), existent in all the Devas; who, having entered into the heart, abides there; and who was born from the elements--this verily is That.
This verse is somewhat obscure and seems like an interpolated amplification of the preceding verse.
VIII
The all-seeing fire which exists hidden in the two sticks, as the foetus is well-guarded in the womb by the mother, (that fire) is to be worshipped day after day by wakeful seekers (after wisdom), as well as by sacrificers. This verily is That.
Fire is called all-seeing because its light makes everything visible. In Vedic sacrifices the altar fire was always kindled by rubbing together two sticks of a special kind of wood called Arani. Because fire was regarded as one of the most perfect symbols of Divine wisdom, it was to be worshipped by all seekers after Truth, whether they followed the path of meditation or the path of rituals.
From whence the sun rises, and whither it goes at setting, upon That all the Devas depend. No one goes beyond That. This verily is That.
What is here (in the visible world), that is there (in the invisible); he who sees difference (between visible and invisible) goes from death to death.
By mind alone this is to be realized. There is no difference whatever (between visible and invisible). He who sees difference here (between these) goes from death to death.
In the sight of true wisdom, there is no difference between the creator and the created. Even physical science has come to recognize that cause and effect are but two aspects of one manifestation of energy. He who fails to see this, being engrossed in the visible only, goes from death to death; because he clings to external forms which are perishable. Only the essence which dwells within is unchangeable and imperishable. This knowledge of the oneness of visible and invisible, however, cannot be acquired through sense-perception. It can only be attained by the purified mind.
XII
The Purusha (Self), of the size of a thumb, resides in the middle of the body as the lord of the past and the future, (he who knows Him) fears no more. This verily is That.
The seat of the Purusha is said to be the heart, hence It "resides in the middle of the body." Although It is limitless and all-pervading, yet in relation to Its abiding-place It is represented as limited in extension, "the size of a thumb." This refers really to the heart, which in shape may be likened to a thumb. Its light is everywhere, yet we see it focused in a lamp and believe it to be there only; similarly, although the life-current flows everywhere in the body, the heart is regarded as peculiarly its seat.
XIII
That Purusha, of the size of a thumb, is like a light without smoke, lord of the past and the future. He is the same today and tomorrow. This verily is That.
In this verse the teacher defines the effulgent nature of the Soul, whose light is pure like a flame without smoke. He also answers the question put by Nachiketas as to what happens after death, by declaring that no real change takes place, because the Soul is ever the same.
XIV
As rain water, (falling) on the mountain top, runs down over the rocks on all sides; similarly, he who sees difference (between visible forms) runs after them in various directions.
O Gautama (Nachiketas), as pure water poured into pure water becomes one, so also is it with the Self of an illumined Knower (he becomes one with the Supreme).
Part Fifth
The city of the Unborn, whose knowledge is unchanging, has eleven gates. Thinking on Him, man grieves no more; and being freed (from ignorance), he attains liberation. This verily is That.
This human body is called a city with eleven gates, where the eternal unborn Spirit dwells. These gates are the two eyes, two ears, two nostrils, the mouth, the navel, the two lower apertures, and the imperceptible opening at the top of the head. The Self or Atman holds the position of ruler in this city; and being above the modifications of birth, death and all human imperfections, It is not affected by the changes of the physical organism. As the intelligent man through constant thought and meditation realizes the splendour of this Supreme Spirit, he becomes free from that part of his nature which grieves and suffers, and thus he attains liberation.
He is the sun dwelling in the bright heaven; He is the air dwelling in space; He is the fire burning on the altar; He is the guest dwelling in the house. He dwells in man. He dwells in those greater than man. He dwells in sacrifice. He dwells in the ether. He is (all that is) born in water, (all that) is born in earth, (all that) is born in sacrifice, (all that) is born on mountains. He is the True and the Great.
III
He it is who sends the (in-coming) Prana (life-breath) upward and throws the (out-going) breath downward. Him all the senses worship, the adorable Atman, seated in the centre (the heart).
When this Atman, which is seated in the body, goes out (from the body), what remains then? This verily is That.
The Upanishads · The Wunder Library — complete classics, free to read, with narration.