Millions and millions of years ago, what was spoken by Kṛṣṇa to the sun god, the same thing was spoken to Arjuna. He said that "I am speaking to you the same old, purātanaṁ yogam, but because the paramparā system is now broken, so I am making again the paramparā system through you, beginning from you." So the paramparā system we can understand by Arjuna's behavior, by Arjuna's understanding. Everything is written in the Bhagavad-gītā. Arjuna accepted Kṛṣṇa, the Supreme Personality of Godhead, paraṁ brahma paraṁ dhāma pavitraṁ paramaṁ bhavān (BG 10.12). So if we follow Arjuna then we can understand Bhagavad-gītā very easily.
So we should not waste. If we keep it for future, then, as it is stated by Prahlāda,
- durāpūreṇa kāmena
- mohena ca balīyasā
- śeṣaṁ gṛheṣu saktasya
- pramattasyāpayāti hi
- (SB 7.6.8)
If you do not practice from the very beginning, it is not possible. Ante nārāyaṇa-smṛtiḥ (SB 2.1.6). It is said that the greatest success of life is at the time of . . . remembering Nārāyaṇa, ante nārāyaṇa-smṛtiḥ. Just like Ajāmila. He, at the end of his life, remembered Nārāyaṇa. So this is success. But this can be possible if we practice from the very beginning. Ajāmila, first of all, he was a brahmacārī, brāhmaṇa, very well behaved brāhmaṇa, learned everything, but due to bad association he fell down. But Kṛṣṇa gave him the opportunity . . . Kṛṣṇa says in the Bhagavad-gītā, na me bhakta praṇaśyati (BG 9.31). If once one has sincerely become the pure devotee of Kṛṣṇa, that will never go in vain.