अन्तवन्त इमे देहा नित्यस्योक्ता: शरीरिण: |
अनाशिनोऽप्रमेयस्य तस्माद्युध्यस्व भारत || 18||
antavanta ime dehā nityasyoktāḥ śharīriṇaḥ
anāśhino ’prameyasya tasmād yudhyasva bhārata
anta-vantaḥ—having an end; ime—these; dehāḥ—material bodies; nityasya—eternally; uktāḥ—are said; śharīriṇaḥ—of the embodied soul; anāśhinaḥ—indestructible; aprameyasya—immeasurable; tasmāt—therefore; yudhyasva—fight; bhārata—descendant of Bharat, Arjun
These bodies which belong to the real imperishable, unknowable Atma are said to be subject to an end; therefore fight, O Arjuna!
Subject to end:- These bodies are subject to death. You are not the body. You are Atma, the indweller, holding the body as a vehicle. So no one should depend on the perishable bodies. You should hold on to Atma, till you obtain the consciousness of your identity with Atma, and cut off the false identification with the body.
Of the embodied: Atma is not far away. He is in and pervading the body, but completely free and uncontaminated by all the modifications of the physical and subtle bodies. Man should constantly cultivate his identity with Atma, and reject the identity with the body (dehAtmabuddhi) and remain as Atma. .
Therefore fight: Since Atma is imperishable, and the bodies are subject to death now or hereafter, the Lord exhorts Arjuna to carry out his duty and fight the battle free from sorrow and fear. The Lord wants his disciple to act in the light of his knowledge of Atma, the perishable nature of material things.
Swami Vivekananda Says —
“As in this life a man begins with childhood, and [passes through youth and old age, so at death he merely passes into another kind of body]. Why should a wise man be sorry?” And where is the beginning of this emotionalism that has got hold of you? It is in the senses. “It is the touch of the senses that brings all this quality of existence: heat and cold, pleasure and pain. They come and go.” Man is miserable this moment, happy the next. As such he cannot experience the nature of the soul.
“Existence can never be non-existence, neither can non-existence ever become existence. … Know, therefore, that that which pervades all this universe is without beginning or end. It is unchangeable. There is nothing in the universe that can change [the Changeless]. Though this body has its beginning and end, the dweller in the body is infinite and without end.”
Knowing this, stand up and fight! Not one step back, that is the idea. … Fight it out, whatever comes. Let the stars move from the sphere! Let the whole world stand against us! Death means only a change of garment. What of it? Thus fight! You gain nothing by becoming cowards. … Taking a step backward, you do not avoid any misfortune. You have cried to all the gods in the world. Has misery ceased? The masses in India cry to sixty million gods, and still die like dogs. Where are these gods? … The gods come to help you when you have succeeded. So what is the use? Die game. … This bending the knee to superstitions, this selling yourself to your own mind does not befit you, my soul. You are infinite, deathless, birthless. Because you are infinite spirit, it does not befit you to be a slave. … Arise! Awake! Stand up and fight! Die if you must. There is none to help you. You are all the world. Who can help you?[Source]
Question: What is the nature of the body?
Answer: It is subject to dissolution and death.
Question: What is Atma, the dweller of the body?
Answer: It is real, imperishable,, and unknowable by the senses and the mind.