Kṛṣṇa was accepted by Arjuna as spiritual master just to teach him what is the actual duty in that war field. So at that time the first śiṣya, śāsana, ruling, He chastised Arjuna by these words, "My dear Arjuna, you are talking just like a very learned man, but no learned man talks like this." That means "You are a fool." He very politely said that, "You are talking with Me as if you are very learned man, but your subject matter is so third class that no learned man takes this subject matter very seriously." What is that? Bodily conception of life. "You are talking just like a very learned man, but your center of activity is the body. So this is not a learn . . . symptom of a learned man."
So if we take this crucial test of learning, we shall find hardly a learned man in this world, hardly one man, because everyone is absorbed in this bodily conception of life. All their ideas—this nationality, humanity, this duty, that duty, all—everything on this. Yasyātma-buddhiḥ kuṇape tri-dhātuke (SB 10.84.13).
They are accepting this bag of skin and bones as self. You see? This is a bag made of skin and bone, and this . . . is spirit soul so cheap thing that it is a bag of skin and bone and some stools and urine, combination? That is nonsense. So hardly you'll find any sane man or any learned man in this world. You see?
So first teaching is that, "You are not this body." That is the beginning of Kṛṣṇa's teaching.
- dehino 'smin yathā dehe
- kaumāraṁ yauvanaṁ jarā
- tathā dehāntaraṁ prāptir
- dhīras tatra na muhyati
- (BG 2.13)
"My dear Arjuna, you are posing yourself as very learned man, but a learned man is not disturbed by this change of body." Just He says very nice example. Just like a child. A child is growing. Growing means he is changing body. A child is born so small—a few years, he becomes big. Now where is that small body? That body is gone. You tell whatever you think, but that body is gone—another body. Then the same child becomes youth, young man. That body is gone. The same man becomes old man. That, that youthful body is gone.
So every second the body is gone, but the soul is there. Anyone knows . . . you can remember; I can remember . . . when I was child, I remember I was doing this. And where is that body? That body is gone, but I am remain . . . why I am remaining? Because I am eternal. I have changed my body, but I am there. Similarly, when I change this body, still I'll be there. This is knowledge. This is nir condition. If in this, during this life, I am changing so many body, so many bodies, still I am there, similarly, it is natural conclusion: when I change this body, I shall remain. I may be in another body. This simple logic is sufficient for a sane man to understand that the living soul is eternal—the body is artificial, dress. By changing dress, one does not die. He is eternal.