Prabhupāda: "And can never be slain." Because it is already described that soul cannot be burned, soul cannot be moistened, soul cannot be dried up, soul cannot be killed, soul cannot be cut into pieces. So many things. Just opposite of matter. Any material thing you take, even stone, iron, it can be burned, it can be cut into pieces, it can dry up, and so many things, all applicable to the matter. But so far the spirit soul is concerned, it is just the opposite. Therefore the conclusion is there, na hanyate hanyamāne śarīre BG 2.20 . Even after this body is annihilated the soul remains eternal. Just like if somebody comes and drives us out of this room, that does not mean that I am finished. I shall go and take shelter of another room. Similarly, when the soul, when the body is killed or annihilated by nature or by force, the soul takes shelter of another body. That is the conclusion. Go on.
Devotee: 31: "Considering your specific duty as a kṣatriya you should know that there is no better engagement for you than fighting on religious principles, and so there is no need for hesitation BG 2.31 ."
Prabhupāda: So here fighting is a matter of duty. That is the kṣatriya spirit. Fighting is not killing. Because people have no idea what is the soul, therefore they think that stopping war will help us in peaceful condition of the society. There are so many troubles so long this body is there. War is one of the items. Even war is stopped, there is no question that people will live forever. No. That is not the law of nature. Duḥkhālayam aśāśvatam BG 8.15 . This life, the problem is how to stop our contact with this material body That is the problem. Not that these general people, they are thinking, "If war, there is no war, then we shall be very happy." How you'll stop your war with māyā ? Māyā has declared war with you, or you have declared war with māyā. Daivī hy eṣā guṇamayī mama māyā duratyayā BG 8.15 . The māyā, the material nature is enforcing, "Why you are closing this door?" "Oh, because it is very cold outside." Who is forcing? Immediately there will be cold, immediately there will be fog, immediately there will be excessive heat, immediately there may be earthquake. How you can stop it? So they simply think... Just like innocent child, they are concerned with the immediate problem. But sane man is concerned with the ultimate problem. So our ultimate problem is not this war. The ultimate problem is repetition of birth and death. That is ultimate problem, how to stop this. That is the problem. So Kṛṣṇa says that "This is useless lamentation, that you do not wish to fight. It is the concluded fact that even your grandfather or relatives die, they will continue as soul. You have to execute your duty. You cannot deviate from your duty." Go on.