Preface: Patience is essential to read this article:

• ☆The article is based on my studies, my concept, my thoughts on the subject. It is further supplemented  with my experiences and self realization.
• ☆I found some link between modern science(Quantum mechanics) and teachings of ancient sages as mentioned in Vedanta, regarding Universe, Supreme Consciousness or the Ultimate truth , the Ultimate Reality whatever we say.
• ☆ The term “MAN” wherever used in this entire text is intended to consider as “HUMAN” irrespective of gender differences.
• ♡ Having gone through the Vedanta/ancient texts, commentaries, translated by different writers, translators, publishers on the same topic, I have tried my best to share the subject matter as I understood and convinced too. My intention is to reach to you with the topic that I found very useful for human lives. I am not good in English literature. Please give your valuable suggestions for the improvement and valuable inputs to make the text beneficial for mankind.
• ☆ The Spiritual context is purely based on ancient sacred texts. Sanskrit slokas are taken from books and websites. There may be little variation in the translations and commentaries. I have shared my own views and explanations according to my concept gathered in the subject through experience and intuitions. There is no discrimination against any religion, race, cast or creed.
• Your feedback will be highly appreciated. I am sure that the subject matter is highly logical and does not bring any conflict. Hope you will enjoy reading. Regards. NAMASTE. I can be reached at : arun7663@gmail.com

Introduction: Death is a Teacher:

Katha Upanishad belongs to Katha Branch of Krishna Yajurveda. Katha Upanishad is a favorite one in all ages and it is placed in third position in the list of Ten Principal Upanishads.

“Katha Upanishad” is divided in two parts( Adhyaya), each part consists of three Vallis(Sections). So far, I have published Valli-1 to Valli-3 of Book-1 and Valli-1 of Book-2. The links are given below:-

1.Essence of Katha Upanishad: Part-1 of 4

2.Essence of Katha Upanishad: Part-2 of 4

3.Essence of Katha Upanishad: Part-3 of 4

4.Essence of Katha Upanishad : Part-4A of 4

In this part, I will discuss in details on BOOK-2; Valli -2

॥ काठकोपनिषदि द्वितीयाध्याये द्वितीया वल्ली ॥

Mantra-1: A City with eleven gates (this body) belongs to the Unborn, Un flickering Consciousness. By meditating on HIM, one does not grieve, He is liberated and being free, He gains emancipation. [  एतद्वै तत् ] This is verily That !

Ekaa-dasha Dwaaram: The Eleven gates of the Body are: Seven openings on the Head[2 Eyes, 2 Ears, 2 Nostrils and 1 Mouth]; Three openings in the lower Body{The Naval, The Genital organ and The Anus}; One opening which is non-physical, positioned at the Crown of the Head, called Brahma-Randhra. 

Brahman: Everything and Everywhere!

Mantra-2: As the SUN, He dwells in the Heavens; as the AIR, He dwells in the Sky; as the FIRE, He dwells in the sacrificial alter (or on Earth); as a guest He dwells in a house. He dwells in Man, He dwells in the Gods, He dwells in the sacrifices, and He dwells in the Sky. He is born in the Water, on the Earth, from the sacrifice, and on the Mountains. HE is all that is True and Great.

Above Mantra teaches on Upasana( Meditation). It reminds that the Self is the same in all beings. That Self has no limits, no boundaries. The Whole Universe is it’s dwelling place.

Brahman: – Director of Prana & Deities:

Mantra-3: He( Brahman) sends Prana upwards; He throws the Apana downwards; that Adorable One seated in the Centre is He, that is worshipped by all the Gods.

Above Mantra gives a focus on the most important function of Supreme Self in our Body which animates by the power and energy provided by Prana, the Vital Life force. There are Five Pranas, among which two are most import which represent the incoming and outgoing Breath. Obviously other three Pranas are implied.

When the Body is negated, what remains?

Mantr-4: As this gets loosened or detached, the embodied Self, the indweller of the Body gets freed from the body. What then remains here? [एतद्वै तत् ] This is verily That !

When Prana is Negated, What Remains?

Mantra-5: Not by Prana, nor by Apana; does any mortal live; but it is some other that they live, on which these two depend.

When the Body Departs, What Remains?

Mantra-6: Well, now I will explain to thee this mysterious and ancient truth about Brahman. You wished to know, when death takes place, what becomes of the Soul? O Gautama?

Following Mantra gives the answer for the Boon-3, which was asked by Nachiketas, which was about the mystery, the secret behind life and death.

Perspective-1: While in ignorance:

Mantra-7: Entering a womb, some embodied Souls are destined to have a Body; other Souls continue only as plants. It all happens as person’s Karma and Knowledge.

Perspective-2: When Knowledge Dawns:

The Purusha remains awake, while we are in sleep, He shapes the countless objects of our desire. He alone is Pure, He is Brahman; He alone is known as the Immortal. In Him rest all the worlds; verily, there is none who can transcend Him. [  एतद्वै तत् ]This is verily That !

The Transcendent Brahman:

Mantra-9 to Mantra-15 will now take you to the Transcendental Realm.

Mantra-9: Just as Fire, though one, entering the world, assumes various forms and shapes; so also the immanent Self of all beings, though one, assumes the form according to each shape it enters, and yet It remains beyond them(is Transcendent) .

Mantra-10: Just as AIR, though one, entering the world, assumes various forms and shapes; so also, the  immanent Self of all beings, though one, assumes the form according to each shape it enters, and yet It remains beyond them(it is Transcendent) .

Mantra-11: Just as the SUN, the eye of the whole world, is not tainted by sight and external defects, the immanent Self of all beings, though one, is not tainted by the sorrows of the world, as it is external to them, (it is Transcendent).

Above three verses teaches us the Upasana on three basic Elements in nature Fire(Agni), Air(Vayu) and The Sun (Sooryah). They are also regarded as the foremost among the Immanence and the Transcendence of the Supreme Self.  Immanence is the Self within a person and Transcendence is the Omnipresent Self.

Being One, Controlling All !

Mantra-12: One Supreme Ruler is the inner Self of all; This one quality appears in all individuals. The wise realize Him in their own hearts. To them belong Eternal Joy, to none else.

Mantra-13: He is the Eternal among the non-eternals, the Intelligence among the intelligent ones; Though One, He fulfil many desires. The wise realize Him in their own hearts. To them is Eternal peace, to none else.

The “Self” is Self-Luminous & Shines Variously:

Mantra-14: Nachiketas asks: “[  एतद्वै तत् ]  “This is That”- thus do the sages perceive; That indescribable highest Bliss. How shall I know That? Does It shine of Itself or does it shine by another light?”

Mantra-15: Lord Yama answers : ” The SUN does not shine there, nor the moon, nor the stars; nor the lightning, much less this lamp. When He shines, everything shines after HIM; by His light, all these Shine!”

॥ इति काठकोपनिषदि द्वितीयाध्याये द्वितीया वल्ली ॥

End of Katha Upanishad Second Book- Section-II(Dwitiya Adhaya: Valli-II)

काठकोपनिषदि द्वितीयाध्याये द्वितीया वल्ली 
        
पुरमेकादशद्वारमजस्यावक्रचेतसः ।
अनुष्ठाय न शोचति विमुक्तश्च विमुच्यते । एतद्वै तत् ॥ १॥

हँसः शुचिषद्वसुरन्तरिक्षसद्-
    होता वेदिषदतिथिर्दुरोणसत् ।
नृषद्वरसदृतसद्व्योमसद्
    अब्जा गोजा ऋतजा अद्रिजा ऋतं बृहत् ॥ २॥

ऊर्ध्वं प्राणमुन्नयत्यपानं प्रत्यगस्यति ।
मध्ये वामनमासीनं विश्वे देवा उपासते ॥ ३॥

अस्य विस्रंसमानस्य शरीरस्थस्य देहिनः ।
देहाद्विमुच्यमानस्य किमत्र परिशिष्यते । एतद्वै तत् ॥ ४॥

न प्राणेन नापानेन मर्त्यो जीवति कश्चन ।
इतरेण तु जीवन्ति यस्मिन्नेतावुपाश्रितौ ॥ ५॥

हन्त त इदं प्रवक्ष्यामि गुह्यं ब्रह्म सनातनम् ।
यथा च मरणं प्राप्य आत्मा भवति गौतम ॥ ६॥

योनिमन्ये प्रपद्यन्ते शरीरत्वाय देहिनः ।
स्थाणुमन्येऽनुसंयन्ति यथाकर्म यथाश्रुतम् ॥ ७॥

य एष सुप्तेषु जागर्ति कामं कामं पुरुषो निर्मिमाणः ।
तदेव शुक्रं तद्ब्रह्म तदेवामृतमुच्यते ।
तस्मिँल्लोकाः श्रिताः सर्वे तदु नात्येति कश्चन । एतद्वै तत् ॥ ८॥

अग्निर्यथैको भुवनं प्रविष्टो
    रूपं रूपं प्रतिरूपो बभूव ।
एकस्तथा सर्वभूतान्तरात्मा
    रूपं रूपं प्रतिरूपो बहिश्च ॥ ९॥

वायुर्यथैको भुवनं प्रविष्टो
    रूपं रूपं प्रतिरूपो बभूव ।
एकस्तथा सर्वभूतान्तरात्मा
    रूपं रूपं प्रतिरूपो बहिश्च ॥ १०॥

सूर्यो यथा सर्वलोकस्य चक्षुः
    न लिप्यते चाक्षुषैर्बाह्यदोषैः ।
एकस्तथा सर्वभूतान्तरात्मा
    न लिप्यते लोकदुःखेन बाह्यः ॥ ११॥

एको वशी सर्वभूतान्तरात्मा
    एकं रूपं बहुधा यः करोति ।
तमात्मस्थं येऽनुपश्यन्ति धीराः
    तेषां सुखं शाश्वतं नेतरेषाम् ॥ १२॥

नित्योऽनित्यानां चेतनश्चेतनानाम्
    एको बहूनां यो विदधाति कामान् ।
तमात्मस्थं येऽनुपश्यन्ति धीराः
    तेषां शान्तिः  शाश्वती नेतरेषाम् ॥ १३॥

तदेतदिति मन्यन्तेऽनिर्देश्यं परमं सुखम् ।
कथं नु तद्विजानीयां किमु भाति विभाति वा ॥ १४॥

न तत्र सूर्यो भाति न चन्द्रतारकं
    नेमा विद्युतो भान्ति कुतोऽयमग्निः ।
तमेव भान्तमनुभाति सर्वं
    तस्य भासा सर्वमिदं विभाति ॥ १५॥

  इति काठकोपनिषदि द्वितीयाध्याये द्वितीया वल्ली ॥

Conclusion:

Failure to comprehend the Essential Unity of Being is the Cause of Rebirth.

Why do we take rebirth or otherwise we can say we move from death to death. Why? It is due to wish of fulfilling desires that remain till death. But if we can realize the True Reality of the Self, the Eternal Self, from whom everything manifests, the desires get vanished, get dried up. All desires melt is the light of the Self. This is Nirvana. Nachiketas wanted to know, what happens to the Souls after death. Lord of Death ” Yama ” explained the reality through conversations between them. That is the Essence of Katha Upanishad.

Recommended readings:

1. Back to the Truth: 5000 years of ADVAITA by Dennis Waite.**
2. THE TEN PRINCIPAL UPANISHADS: Translated by Shree Purohit** Swami and W.B.Yeats
3. Brahma Sutra Bhasya of Sankaracharya: Translated by Swami Gambhirananda.**
4. Commentary of Katha Upanishad: By Swami Krishnananda.
5. Katha Upanishad: By Swami GuruBhaktananda.
6. EIGHT UPANISADS -VOL-1 with commentary of Sankaracharya, Translated by SWAMI GAMBHIRANANDA.
7. THE TAITTIRIYA UPANISHAD: SHIKSHAVALLI-ANANDAVALLI-BHRIGUVALLI with Sri Shankara’s Commentary By Sri Swami Satchidanandera Saraswati.
8. Commentary of Mandukya Upanishad: By Swami Krishnananda.
9. MANDUKYA Upanishad By Swami GuruBhaktananda.
10. A-U-M Awakening to Reality : By Dennis Waite***
11. Panchadasi: Swami Vidyaranya: 
12. Information available on internet.

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