The term Upanishad is derived from upa (near), ni (down) and s(h)ad (to sit), i.e., sitting down near and discuss about search of enlightment. There are more than 200 known Upanishads. Katha Upanishad is the teaching about Self-knowledge, the separation of the human soul (the supreme Self) from the body, by the god of Death, Yama to Nachiketa.
The word 'Nachiketa' has various meanings which are interrelated with its other meanings.
(a) That which is unperceived.
(b) The quickening Spirit that lies within all things like fire, latent in wood, the spirit that gives, the unquenchable thirst for the unknown
(d) The one who is continuously looking for nothing but an unending spiritual energy
Nachiketa is the son of King Vajashravas. Vajashravas performed a Yaga to attain heaven. During Yaga one has to donate everything what ever he has. But Vajashravas donated weak cows. The concept of Yaga is who ever is related in the donation both should be favoured. But Vajashravas donation did not make any sense for his son Nachiketa. Although young, he was mature in understand ing, knowledge and faith. He knew that after a yagna cows should indeed be donated, and it would be wrong not to do so. But giving away things that are a burden to oneself is not donation. Instead the giver himself becomes misfortuned. The finest and dearest things should be donated. This donation of weak cows by my father is not proper.
‘One who donates cows that cannot even drink water, cannot eat grass, cannot even give milk and have aged, attains the loka (realm) named ‘Anandã’, i.e. ‘where there is no bliss’ (Katha Upanishad 1/1/3). Nachiketa thought that by giving such worthless donations, his father will also attain such a miseryfilled loka. With such feelings, Nachiketa, who cared for his father, was pained deeply. To stop his father’s undesirable actions, he asked "O Father! I am also a part of your wealth. Whom will you give me to?"
His father did not reply. Nachiketa repeated the question, ‘Father! Whom will you give me to?’ His father stilled paid no attention. When Nachiketa asked for the third time his father became angry and said, ‘I give you to Yama (Death)’ This sentence was meant to convey the message, ‘Go away, don’t bother me right now.’ But Nachiketa was an ideal son and he thought that regardless of the fact that his father had said this in a fit of anger, his words should not go unobeyed. Hence, Nachiketa decided to go to the god of Death, Yama Raja. His father found out and tried to stop him. However, Nachiketa felt that his father was trying to stop him due to the fear of death. He dumbfounded his father with an eternal truth. He said, ‘O father! Those before us have all died. Those present and those in the future will also die. Because we are mortals, like plants we grow and die. So don’t worry, think about the tendency of death and let me do as you said’ (Katha Upanishad:1/1/6). His father gave him permission. Nachiketa set off towards the palace of Yama Raja.
Nachiketa reached the palace of Yama Raja only to find that Yama Raja was away. He waited for three days without any food or water for Yama Raja to return. On the day after the third night, Yama Raja arrived. His old servants informed him of the unique young guest and suggested that he provide him some hospitality. Yama Raja did so. He pleased the child with water to wash his feet, flowers, a meal, etc. He also made a request, ‘O Brahmin child! You are worthy of being offered prostrations. You have come to my palace as a guest. I am pained that you had to spend three nights without any food or water. This was a grave mistake, since a guest should be well looked after. Therefore, O Brahmin!
For my offence to be forgiven and that I may be liberated, I bow to you and request that you ask for three boons in return for the three nights you spent fasting’ (Katha Upanishad: 1/1/9).
Pleased with Yama Raja’s generosity, the young Brahmin, Nachiketa, asked for his first boon. Yama Raja, This is the first of the three boons that I ask for. Let my father’s thoughts come to rest. Let him be pleased with me and free of anger towards me. When I leave you and go home, let him recognize me as “his son”. Let him talk to me with the same love and affection as he did before. Hearing this, Yama was delighted, since at such a young age he had asked for something which even elders would not have thought of. Pleased, Yama Raja granted him his first wish.
Before asking for the second boon, the Nachiketa clarified, ‘O Death! There is no fear in the abode of Paramatma. Even you, Death, are not there. Therefore there is no fear of things like old age. In Paramatma’s abode there are not even any bodily feelings like hunger and thirst. It is a place full of supreme bliss. Therefore, muktas (liberated jivas) who are above all misery experience bliss there’ (Katha Upanishad: 1/1/12). Hence, O Yama Raja! ‘This is what I ask for as my second boon’ You know agnividya by which one can attain that abode of Paramatma, teach it to me’ (Katha Upanishad: 1/1/13). Yama Raja readily agreed and became a teacher. He taught him agnividya.
Asking for the third boon, Nachiketa says, ‘O Yama Raja! There is one discussion that arises time and time again in the world and that is regarding matters after death. Some say there is nothing after death. Some say that there is something after death. Please give me a clear decision on this matter. This is the third boon I ask for’. Nachiketa did not ask this question because he doubted whether there was something after death or not. This is clearly reflected from his talks to Yama Raja in his previous boon. His reason for asking is that the common person is generally baffled on hearing contradictory things. Sometimes, so called intelligent people, due to their arrogance, mislead gullible people with false logic. They confuse people by creating doubts regarding accepted facts by claiming that they are blind faith, a matter of sentimentalism or false. Thus, Nachiketa requests, ‘Therefore, O Yama Raja! You are a wise and skilled orator. Whatever you approve will be accepted by all. The true principle will be revealed by your words. People will also recognize what is false. They will identify empty shows of words and webs of logic. People’s conviction in the truth will become stronger. Therefore, O Death! You yourself explain to me the secrets of life after death.’ This is Nachiketa’s noble and humble request.
Hearing this Yama Raja tried to convince Nachiketa saying
Ask me for you and your generations to live for 100 years - I will give
Ask me Cows, Horses and Elephants - I will give
Ask me more Gold or land - I will give
You live as long as you wish and want to live - I will bless
Or else, Ask me any wish equal to the above
Or I will make you a king for a kingdom and you can rule it and have all kinds of wealth
Let me also give you the chariots and heavenly womens which others cant even think of; But the answer for the third boom you ask for, is not even known by the Godly peoples (Devas) initially. but Nachiketa says O Yama Raj, human life is short, keep the worldly wealth and pleasures to himself, declares that pompous wealth, lust and pleasures are fleeting and vain, then insists on his third boom.
Knowing that there is no other go, Yama Raj starts to grant the third boom. He begins his teaching by distinguishing between preya (dear, pleasant) and shreya ( good, beneficial excellence)
Different is the good and different is the dear,
they both, having different aims, fetter you men;
He, who chooses for himself the good, comes to wellbeing,
he, who chooses the dear, loses the goal.
The good and the dear approach the man,
The wise man, pondering over both, distinguishes them;
The wise one chooses the good over the dear,
The fool, acquisitive and craving, chooses the dear.
— Yama, Katha Upanishad, 1.2.1-1.2.2
The verses 1.2.4 through 1.2.6 of Katha Upanishad then characterizes Knowledge/Wisdom as the pursuit of good, and Ignorance/Delusion as the pursuit of pleasant. The verses 1.2.7 through 1.2.11 of Katha Upanishad state Knowledge/Wisdom and the pursuit of good is difficult yet eternal, while Ignorance/Delusion and the pursuit of the pleasant is easy yet transient. Knowledge requires effort, and often not comprehended by man even when he reads it or hears it or by internal argument. The pursuit of Knowledge and the good, can be taught, learnt and thus realized.
He (the Atman), difficult to be seen, full of mystery,
the Ancient, primaeval one, concealed deep within,
He who, by yoga means of meditation on his self, comprehends Atman within him as God,
He leaves joy and sorrow far behind.
— Katha Upanishad, 1.2.12
Atman – Soul, Self – exists, though it is invisible and full of mystery is ancient, and recognizable by Yoga (meditation on one's self). In verses 1.2.14 through 1.2.22, the Katha Upanishad asserts that the essence of Veda is make man liberated and free, look past what has happened and what has not happened, free from the past and the future, refocus his attention past Ignorance to Knowledge, to the means of blissful existence beyond joy and sorrow.
In final verses of the second Valli, the Katha Upanishad asserts that Atman-knowledge, or Self-realization, is not attained by instruction, not arguments nor reasoning from scriptures. It is comprehended by oneself through meditation and introspection. It is not attained by those who do not abstain from misconduct, not those who are restless nor composed, not those whose mind is not calm and tranquil, but only those who live ethically, are composed, tranquil, internally peaceful, search within and examine their own nature.
The Katha Upanishad asserts that one who does not use his powers of reasoning, whose senses are unruly and mind unbridled, his life drifts in chaos and confusion, his existence entangled in samsara. Those who use their intelligence, have their senses calm and under reason, they live a life of bliss and liberation, which is the highest place of Vishnu. Atman, asserts Katha Upanishad, is the subject of Self-knowledge, the bearer of spiritual reality, that which is all-prevading, inside every being, that unifies all human beings as well as all creatures, the concealed, eternal, immortal, pure bliss. It exists and active when man is in awake-state, it exists and active when man is in dream-state.
According to hindu mythology, Nachiketa learnt what happens after death from Lord Yama by means of Upanishad. Upanishad means the inner or mystic teaching.