So anyway, Arjuna, when he heard Bhagavad-gītā very minutely, he was asked by Kṛṣṇa, "Now I have explained to you the Bhagavad-gītā, the knowledge, the spiritual knowledge. Now whatever you like, you can do." Yathecchasi tathā kuru (BG 18.63): "Whatever you like. Now it is up to you. If you don't fight, that you can decide. I have no objection, because you have got little independence. But My advice is that you should fight. Now I ask you what you are going to do." So Arjuna replied that naṣṭo mohaḥ smṛtir labdhā tvat-prasādān madhusudana, kariṣye vacanaṁ tava (BG 18.73): "Now I shall do it." This is Bhagavad-gītā. This is bhakti, that we have to act according to the advice of the Supreme Lord. That is bhakti. Hṛṣīkeṇa hṛṣīkeśa-sevanaṁ bhaktir ucyate (CC Madhya 19.170).
So therefore we have to first of all establish our relationship with God. Your establish . . . is already established. Just like the father and the son—the relationship is already there. It is not . . . but still, sometimes the son goes out of home and may be forgetting his father. Similarly, we are out of home. We have come from the spiritual world in this material world. We have forgotten our father. So we have to revive this relationship with our father, or God, or Kṛṣṇa. That is the main business of human life. In other species of life lower than the human being it is not possible to revive our old relationship with God. But in this life . . . therefore this is the greatest opportunity. After all, we are under the grip of material nature's law. That is explained in there. Tathā dehāntara-prāptiḥ (BG 2.13). According to our desire, we are creating a different type of body, and after death, tathā dehāntara-prāptiḥ . . . just like the child is become a boy, the boy is becoming young man, the young man is becoming middle-aged man, and the middle-aged man is becoming old man. So what is next after the old body? The next is tathā dehāntara-prāptiḥ: you have to accept another body. This is called chain or cycle of birth and death, or transmigration of the soul. This is going on.
So if you want to . . . but nobody wants to die. Nobody wants to change this body. But this is a problem. One should know it. That is the first instruction given by Kṛṣṇa . . . (break) . . . Arjuna, that we are changing. Tathā dehāntara-prāptiḥ. So this is the opportunity, human life. If we want to stop this repetition of birth and death under different obligation and different circumstances, we should take instruction from Kṛṣṇa, try to understand Kṛṣṇa—that is Bhagavad-gītā—and make our life successful so that . . . understanding Kṛṣṇa means, as it is stated, tyaktvā dehaṁ punar janma naiti mām eti kaunteya (BG 4.9).