The wise, who by means of the highest meditation on the Self knows the Ancient One, difficult to perceive, seated in the innermost recess, hidden in the cave of the heart, dwelling in the depth of inner being, (he who knows that One) as God, is liberated from the fetters of joy and sorrow.
XIII
A mortal, having heard and fully grasped this, and having realized through discrimination the subtle Self, rejoices, because he has obtained that which is the source of all joy. I think the abode (of Truth) is open to Nachiketas.
The Scriptures give three stages in all spiritual attainment. The aspirant must first hear about the Truth from an enlightened teacher; next he must reflect upon what he has heard; then by constant practice of discrimination and meditation he realizes it; and with realization comes the fulfilment of every desire, because it unites him with the source of all. Having beheld this, a man learns that all sense pleasures are but fragmentary reflections of that one supreme joy, which can be found in the true Self alone. Yama assures Nachiketas that there is no doubt of his realizing the Truth, because he has shown the highest discrimination as well as fixity of purpose.
XIV
Nachiketas said: That which thou seest, which is neither virtue nor vice, neither cause nor effect, neither past nor future (but beyond these), tell me That.
XV
Yama replied: That goal which all the Vedas glorify, which all austerities proclaim, desiring which (people) practice Brahmacharya (a life of continence and service), that goal I tell thee briefly—it is Aum.
What name can man give to God? How can the Infinite be bound by any finite word? All that language can express must be finite, since it is itself finite. Yet it is very difficult for mortals to think or speak of anything without calling it by a definite name. Knowing this, the Sages gave to the Supreme the name A-U-M which stands as the root of all language. The first letter "A" is the mother-sound, being the natural sound uttered by every creature when the throat is opened, and no sound can be made without opening the throat. The last letter "M," spoken by closing the lips, terminates all articulation. As one carries the sound from the throat to the lips, it passes through the sound "U." These three sounds therefore cover the whole field of possible articulate sound. Their combination is called the Akshara or the imperishable word, the Sound-Brahman or the Word God, because it is the most universal name which can be given to the Supreme. Hence it must be the word which was "in the beginning" and corresponds to the Logos of Christian theology. It is because of the all-embracing significance of this name that it is used so universally in the Vedic Scriptures to designate the Absolute.