If a man knows the self as "I am this," then desiring what and for whose sake will he suffer in the wake of the body? Whoever has realized and intimately known the Self, which has entered this perilous and perplexing place, is the maker of the universe; for he is the maker of all. All is his Self, and he, again, is indeed the Self of all. Those who know Brahman become immortal, while others only suffer misery. When a person following a teacher's instructions directly beholds the effulgent SelfÑthe Lord of all that has been and will beÑhe no longer wishes to hide himself from It. That in which the five groups of five and the akasha rest, that very Atman (the soul) I regard as the Immortal Brahman. Knowing that Brahman, I am immortal. They who know the Vital Breath (Prana) of the vital breath (prana), the Eye of the eye, the Ear of the ear, the Mind of the mind, have realized the ancient, primordial Brahman.
Through the mind alone is Brahman to be realized. There is in It no diversity. He goes from death to death who sees in It, as it were, diversity. Unknowable and constant, It should be realized in one form only. The Self is free from taint, beyond the akasha, birthless, infinite and unchanging. The intelligent seeker of Brahman, learning about the Self alone, should practice wisdom (prajna). Let him not think of too many words, for that is exhausting to the organ of speech.
That great, unborn Self, which is identified with the intellect (vijnanamaya) and which dwells in the midst of the organs, lies in the akasha within the heart. It is the controller of all, the lord of all, the ruler of all. It does not become greater through good deeds or smaller through evil deeds. It is the lord of all beings, the ruler of all beings, the protector of all beings. It is the dam that serves as the boundary to keep the different worlds apart. The brahmins seek to realize It through the study of the Vedas, through sacrifices, through gifts, and through austerity which does not lead to annihilation. Knowing It alone, one becomes a sage (muni).
Wishing for this World (i.e., the Self) alone, monks renounce their homes. The knowers of Brahman of olden times, it is said, did not wish for offspring. They thought, "What shall we do with offspringÑwe who have attained this Self, this World?" They gave up, it is said, their desire for sons, for wealth, and for the worlds, and led the life of religious mendicants. That which is the desire for sons is the desire for wealth, and that which is the desire for wealth is the desire for the worlds; for both these, indeed, are but desires.
This Self is That which has been described as neti, neti, "not this, not this." It is imperceptible, for It is not perceived; undecaying, for It never decays; unattached, for It is never attached; unfettered, for It never feels pain and never suffers injury. This has been expressed by the following Rig verse: "This is the eternal glory of Brahman: It neither increases nor decreases through work. Therefore one should know the nature of That alone. Knowing It, one is not touched by evil action."
Therefore, he who knows It as such becomes self-controlled, calm, withdrawn into himself, patient and collected; he sees the Self in his own self (body); he sees all as the Self. Evil does not overcome him, but he overcomes all evil. Evil does not afflict him, but he consumes all evil. He becomes sinless, taintless, free from doubts, a true Brahmana (knower of Brahman). That great, unborn Self is undecaying, immortal, undying, fearless; It is Brahman (infinite). Brahman is indeed fearless. He who knows It as such becomes the fearless Brahman.
Shukla Yajur Veda, Brihadaranyaka Upanishad 4.4.12-25
Commentary by Swami Nikhilananda
It may be contended that there is a contradiction in the two statements, namely, that Brahman is unknowable and that It should be known. The contention is not valid. When it is said that Brahman is unknowable, the statement means that Brahman cannot be known as an object by the ordinary means of knowledge. Again, when it is said that Brahman should be known, the statement means that Brahman can be known only through scriptural evidence. The scriptures, too, describe Brahman by the denial of such attributes as if It is the subject or the object of knowledge. They do not speak of Brahman as an object. The "knowledge of Brahman" really means the cessation of Its identification with extraneous objects, such as the body and organs. It is the knowledge of identity with Atman. Such identity is not to be attained; it always exists but remains hidden because of the false identification with the body, organs, etc. When the false identity is destroyed, the natural identification of the Self with Brahman is revealed. This is expressed by the statement "The Self is known."
Swami Nikhilananda (1895-1973), was founder and spiritual leader of the Ramakrishna-Vivekananda Center of New York from 1933 to his Mahasamadhi in 1973. His four-volume Upanishad translation was completed in 1959.
The Vedas are the divinely revealed and most revered scriptures, sruti, of Hinduism, likened to the Torah (1,200 bce), Bible New Testament (100 ce), Koran (630 ce) or Zend Avesta (600 bce). Four in number, Rig, Yajur, Sama and Atharva, the Vedas include over 100,000 verses. Oldest portions may date back as far as 6,000 BCE