"So if you want to stop the danger of death, then you have to understand what is that Absolute Truth. Just like I have given already the example of sunshine. If you come to the sunshine, there is no darkness. But if you keep yourself within closed door, do not like to see the sunshine, that is your own choice. So everyone should try to come to the light. That is Vedic injunction: tamaso mā jyotir gamaya, means 'Do not remain in darkness; come to the light.' Light means knowledge, and darkness means ignorance. So every one of us now in the ignorance that we do not know 'What I am.' Everyone is in darkness in the concept of body. Ask anyone what you are. He will say, 'I am this body. I am Mr. Such-and-such,' 'I am Indian,' 'I am American.' This is all bodily description. And we have already discussed: this body is temporary, but I, the spirit soul, I am permanent. I have already experienced that I had my childhood body, I had my babyhood body, I had my boyhood body, youthhood body. I know it. But the bodies are no more existing, but I am existing. So therefore I am permanent, and the body is nonpermanent. Therefore it is said, nāsato vidyate bhāvaḥ: 'Permanency is not there in the body.' Nābhāvo vidyate sataḥ: 'And there is no annihilation of the permanent or the eternal.'
So this is... Kṛṣṇa, although He is the authority, still, He says that ubhayor api dṛṣṭaḥ antaḥ tu anayos tattva-darśibhiḥ. He says, 'All the tattva-darśī, the knower of the Absolute Truth, they know it very well, and they have decided like that.' The purpose is that we have to accept the experience of the tattva-darśī, of the seer of the Absolute Truth. That is knowledge. Our knowledge is imperfect because our senses are imperfect. Therefore we do not come to the right knowledge by exercising our senses. The idea is that we should accept the statement of Kṛṣṇa and the śāstra that we or I or you, we are spirit soul; we are permanent. And the body is not permanent. But we should be intelligent enough how we can get the condition of permanence. That is possible when you or I, we come to the platform of eternity. That is explained in another place of Śrīmad Bhagavad-gītā, bahavo jñāna-tapasā pūtā mad-bhāvam ādigacchati, like that. Means that 'Many persons, by cultivating knowledge and tapasya, jñāna-tapasā, pūtāḥ, became purified. They have got the same status like Me.' The same status means God is eternal, God is full of knowledge and God is full of bliss.
So we are all part and parcel of God. We are part and parcel of God; therefore we have got the same quality, just like a particle of gold has got the same quality as the big gold, and the small drop of seawater has got the same chemical composition as the large mass water. That God is sac-cid-ānanda-vigrahaḥ (Bs. 5.1), eternal, full of bliss and knowledge, we can also attain that stage by purifying ourself. That purificatory process is stated as jñāna-tapasā, means knowledge and austerity. We can come to the real knowledge of our existence by purifying ourself. The purificatory process we are introducing by this Kṛṣṇa consciousness movement. And the method is very simple: chanting Hare Kṛṣṇa mantra. The more you chant this mahā-mantra, or the transcendental vibration Hare Kṛṣṇa, you become purified. Then you can understand what you are. Then every one of us, we can understand that 'I am not this body. I am not American. I am not Indian. I am not Mexican. I am spirit soul.'
This stage is called brahma-bhūtaḥ, means self-realization. That is stated in the Bhagavad-gītā, brahma-bhūtaḥ prasannātmā (BG 18.54), means as soon as you are self-realized, you become jubilant. In the bodily concept of life we are always full of anxiety and morose. Yes. That is the material condition. But as soon as you realize yourself that you are not this body, you are different from this body, you become jubilant. Brahma-bhūtaḥ prasannātmā. This means as soon as one is self-realized, immediately he becomes happy, jubilant. And what is the symptom of becoming jubilant? That is also stated, na śocati na kāṅkṣati: 'He does not hanker after anything, neither he laments for any loss.' In the material condition we are in the platform of lamentation and hankering. Everyone is trying to possess something which he does not possess, and everyone is lamenting after losing his possession. These are the condition of the materialistic person. So Brahman realization, or self-realization, means no longer lamentation, no longer hankering."
(Srila Prabhupada Lecture, Mexico City, February 16, 1975)