Disclaimer:

• ☆This article is purely based on my studies, my thoughts, my concept, my beliefs, 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.

Katha Upanishad : —  It gives a direct teaching to the spiritual aspirant.

ॐ ॥ अथ कठोपनिषद् ॥

Peace Invocation:-

ॐ सह नाववतु । सह नौ भुनक्तु । सहवीर्यं करवावहै ।
तेजस्वि नावधीतमस्तु । मा विद्विषावहै ॥
  ॐ शान्तिः शान्तिः शान्तिः ॥
May HE protect us both. May HE take pleasure in us both. May we show courage together. May spiritual knowledge shine before us. May we never hate one another. May peace and peace and peace be everywhere.

॥ प्रथमाध्याये तृतीया वल्ली॥  Introduction: 

This third section is very important for the seekers. Deals with process of Sadhana. How can an aspirant transcends himself ? Section-1: [ Essence of Katha Upanishad part-1 of 4 ] was an introduction on Nachiketas’ position. Section-2 [ Essence of Katha Upanishad part-2 of 4 ] introduced the existence of the Supreme Being. Now an extended Metaphor is introduced in this section to make the Text easy. Section has 17 verses. All verses are discussed.  Let us look into:

Two Selves :The Universal Self and The Individual Self: 

Two Selves:  One is in the process of attaining: The attainer. Other is that what to be attained. One is Traveller , other is Destination. Obviously between two the common is means of communication and that is “CHARIOT”.

ऋतं पिबन्तौ सुकृतस्य लोके
    गुहां प्रविष्टौ परमे परार्धे ।
छायातपौ ब्रह्मविदो वदन्ति
    पञ्चाग्नयो ये च त्रिणाचिकेताः ॥ १॥

यः सेतुरीजानानामक्षरं ब्रह्म यत् परम् ।
अभयं तितीर्षतां पारं नाचिकेतँ शकेमहि ॥ २॥

Both the Individual Self and the Universal Self, are living in the heart, like shade and Light. Though beyond enjoyment, yet enjoy the fruit of action. Wise says this for the knowers of Brahman and the performers of the Nachiketas fire ( त्रिणाचिकेताः ~ trinachiketaah). [1.3.1]. The Heart here is referred to the Intellect, where the Supreme Self gets reflected and that reflection is Jiva or Ego (Ahamkara). “पञ्चाग्नयो~ pancha-agnayah refers here to the performers of the five fires, the house holders, the followers of Karma Kanda of Vedas. And  those who performs त्रिणाचिकेताः ~ trinachiketaah are worshipper of Upasana Kanda of Vedas. Man can kindle that Fire, that Spirit, a bridge for all who sacrifice, a guide for all who pass beyond fear.[1.3.2]

आत्मानँ रथितं विद्धि शरीरँ रथमेव तु ।
बुद्धिं तु सारथिं विद्धि मनः प्रग्रहमेव च ॥ ३॥

इन्द्रियाणि हयानाहुर्विषयाँ स्तेषु गोचरान् ।
आत्मेन्द्रियमनोयुक्तं भोक्तेत्याहुर्मनीषिणः ॥ ४॥

Know the Atman to be the master of the Chariot; the body, the chariot; the Intellect (buddhi) , the charioteer ; and the mind , the reins. The senses, they say , are the horses; the objects, the roads. When Self is joined to body, mind, sense, none but He enjoys. [1.3.3-4]

The Intellect: Avijnanvan and Vijnanavan:

यस्त्वविज्ञानवान्भवत्ययुक्तेन मनसा सदा ।
तस्येन्द्रियाण्यवश्यानि दुष्टाश्वा इव सारथेः ॥ ५॥

यस्तु विज्ञानवान्भवति युक्तेन मनसा सदा ।
तस्येन्द्रियाणि वश्यानि सदश्वा इव सारथेः ॥ ६॥

When a man lack steadiness, unable to control his mind, his senses are like unmanageable horses.  यस्त्वविज्ञानवान्भवत्ययुक्तेन~  “avijnaanavaan bhavati” means non-discriminating intellect and विज्ञानवान्भवति =  discriminating intellect. The non-discriminating charioteer is most dangerous. The discriminating one takes care to rein in the mind so that the horses are well-controlled.[1.3.5-6 ]

The Destination: Reaching the Goal:

यस्त्वविज्ञानवान्भवत्यमनस्कः सदाऽशुचिः ।
न स तत्पदमाप्नोति संसारं चाधिगच्छति ॥ ७॥

यस्तु विज्ञानवान्भवति समनस्कः सदा शुचिः ।
स तु तत्पदमाप्नोति यस्माद्भूयो न जायते ॥ ८॥

विज्ञानसारथिर्यस्तु मनः प्रग्रहवान्नरः । 
सोऽध्वनः पारमाप्नोति तद्विष्णोः परमं पदम् ॥ ९॥

Three verses: 1.3.7 to 1.3.9 focus on the Destination, where the intellect is the key factor. The impure, self-willed, unsteady  man misses the goal and is born again and again. The self-controlled , steady, pure man goes to that Goal from which he never returns. He who calls intellect to manage the reins of his mind reaches the end of his journey, finds that Supreme abode of Vishnu.[ 1.3.7-9] 

The Route of the Journey: 

इन्द्रियेभ्यः परा ह्यर्था अर्थेभ्यश्च परं मनः ।
मनसस्तु परा बुद्धिर्बुद्धेरात्मा महान्परः ॥ १०

महतः परमव्यक्तमव्यक्तात्पुरुषः परः । 
पुरुषान्न परं किंचित्सा काष्ठा सा परा गतिः ॥ ११॥ 

Above the senses are the objects of desire, above the objects of desire is mind, above the mind is intellect, above the intellect manifest the great Atman, beyond the great Atman, the unmanifest, the Purusha. Beyond the Purusha, there is nothing. That is the END, the Supreme Goal. [1.3.10-11]

Here the journey is through understanding and reaching deeper levels within our Being. No physical distance needs to be covered. Only to meditate on ॐ (AUM) going deeper and subtler till it reaches the core. 

Self is seen only by Subtle intellect:

एष सर्वेषु भूतेषु गूढोऽऽत्मा न प्रकाशते ।
दृश्यते त्वग्र्यया बुद्ध्या सूक्ष्मया सूक्ष्मदर्शिभिः ॥ १२॥

This Atman is in all living beings. It is hidden there and not visible to eye (गूढोऽऽत्मा न प्रकाशते ). It can indeed be  seen by the sharp intellect with the subtle vision(बुद्ध्या सूक्ष्मया सूक्ष्मदर्शिभिः) [1.3.12]. Intellect of the sage finds Him.

Successive Merging from Speech to Self:

यच्छेद्वाङ्मनसी प्राज्ञस्तद्यच्छेज्ज्ञान आत्मनि ।
ज्ञानमात्मनि महति नियच्छेत्तद्यच्छेच्छान्त आत्मनि ॥ १३॥

उत्तिष्ठत जाग्रत
    प्राप्य वरान्निबोधत ।
क्षुरस्य धारा निशिता दुरत्यया
    दुर्गं पथस्तत्कवयो वदन्ति ॥ १४॥

The wise nature in  man would loose his speech in mind, mind in the intellect, intellect into the “Mahat” and the Mahat into The Peaceful Self. Arise, awake! Learn Wisdom at Master’s feet. The path is indeed difficult to cross and hard to tread, like the sharp edge of a razor. Mahat here is referred to the total MIND [1.3.13-14] { Please see the notes at the end}.

Subtlety of the Supreme Self:

अशब्दमस्पर्शमरूपमव्ययं
    तथाऽरसं नित्यमगन्धवच्च यत् ।
अनाद्यनन्तं महतः परं ध्रुवं
    निचाय्य तन्मृत्युमुखात् प्रमुच्यते ॥ १५॥

He who knows the soundless, odorless, tasteless,  intangible, formless, deathless, supernatural, unchangeable Reality, springs out of the mouth of Death.(1.3.15).

Glory of the ” Nachiketas ” Knowledge:

नाचिकेतमुपाख्यानं मृत्युप्रोक्तँ सनातनम् । 
उक्त्वा श्रुत्वा च मेधावी ब्रह्मलोके महीयते ॥ १६॥

य इमं परमं गुह्यं श्रावयेद् ब्रह्मसंसदि । 
प्रयतः श्राद्धकाले वा तदानन्त्याय कल्पते । 
तदानन्त्याय कल्पत इति ॥ १७॥

This Vedic knowledge as received by Nachiketas, and as told by the Lord of Death is Eternal. Those who hear and repeat correctly this ancient dialogue becomes worthy of glorification in the world of Brahman( Brahma Loka). He who sings this great mystery at the anniversary of his fathers to a rightly chosen company, finds good luck, good luck beyond measure.[1.3.16-17]

Conclusion:

The highest evolute in creation is Mahat. Then comes ahankara; then comes the tanmatras and then, at last, the five elements. But to us , the five elements come first. And as the world affects our thinking and perception, we are slaves of it. The jive is enslaved by Avidya (ignorance). Avidya has to be removed. Absence of knowledge brings fear of Death. With vidya( knowledge), people become fearless. Knowing this knowledge, people will welcome Lord of Death, Yama, not repel Him.

॥ इति काठकोपनिषदि प्रथमाध्याये तृतीया वल्ली ॥***End of Second Valli of first Adhaya***

Thus ends the Third Chapter of the First Part of the Katha Upanishad.

Notes:-

• a) Tanmatras are the 5 objects of perception, made up of the five subtle elements.
• b) Mahat: Beyond the senses there are objects. Beyond the objects is mind, beyond the mind is intellect. Beyond the intellect is Great Self Mahat(cosmic intelligence).

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. Information available on internet.

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