Bhagavad Gita Chapter 2 - Samkhya Yoga - Sloka 18

The entire content of this mail is from Swami Chidbhavananda's translation of  The Bhagavad Gita, published by Ramakrishna Mission.

The Real and the Unreal Sloka 16-20

1 Gita Sloka every day - Chapter 2 - Samkhya Yoga - Sloka 18

Anta vantah ime deha nityasya uktah sharirinah I

Anashinah aprameyasya tasmat yudhyasva bharata II sloka 18

अन्त वन्तः इमे देहाःनित्यस्य उक्ताः शरीरिणः ।

अनाशिनः अप्रमेयस्य तस्मात युध्यस्व भारत ।। श्लोक १८ 

These bodies of the Indweller, who is eternal, indestructible and immeasurable, are said to have an end. Fight therefore, O Bharata. 

The ocean is ever itself. A portion of the water in it changes place forming waves on the surface and currents below. Elsewhere it freezes as icebergs. Changes of this kind take place in nature; but Atman doesnot undergo any chnage whatsoever, it being eternal. All the water in a pond evaporates and disappears. But Atman is not exposed to this kind of destruction; it is therefore indestructible. Body can be cognised and described; but Atman is beyond the domain of the mind and speech; so it is immeasurable.

Because of delusion over earthly relationships and over things earthly, Arjuna chooses to recoil from the righteous war. It ill behoves him to abandonhis duty. So the Lord exhorts him, "Fight O Bharata". This exhortation can be found again and again as the burden of the Gita