(Manohara—click to enlarge)
Prabhupāda: This science is unknown to the rascals. Yaṁ yaṁ vāpi smaran bhāvaṁ tyajaty ante kalevaram (BG 8.6). At the time of death, your position of the mind will create the next body. This is the science. So if you create your the position of the mind, Kṛṣṇa conscious, then you will get a body like Kṛṣṇa, sac-cid-ānanda-vigraha (Bs. 5.1). This is Kṛṣṇa consciousness movement, that "Why you shall love dog and cats? Love God, Kṛṣṇa, and you get the next body like a Kṛṣṇa." Sac-cid-ānanda-vigraha. Anādir ādir govindaḥ sarva-kāraṇa-kāraṇam (Bs. 5.1). This is Kṛṣṇa consciousness movement, how to think of Kṛṣṇa at the time of death. Then your life is successful.
So that has to be practiced. Sadā tad-bhāva-bhāvitaḥ (BG 8.6). If you always chant Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare, that means you remember Kṛṣṇa always. So there is chance, ninety-nine percent chance, that at the time of your death you will think of Kṛṣṇa and your life is successful. Very simple method. Make always your mind absorbed in Kṛṣṇa; naturally at the time of death you will think of Kṛṣṇa. Mad-yājino 'pi yānti mām (BG 9.25). That is confirmed in the Bhagavad-gītā. Tyaktvā dehaṁ punar janma naiti mām iti kaunteya (BG 4.9). Such person, Kṛṣṇa conscious person, who knows Kṛṣṇa...
If you think of Kṛṣṇa, naturally you know of Kṛṣṇa. You know of Kṛṣṇa. Kṛṣṇa is within your heart. So if you think of Kṛṣṇa, then gradually you become Kṛṣṇa-ized. Just like you put the iron rod in the fire. Gradually it becomes fire—warm, warmer, warmer, then red-hot. When it is red-hot it is fire. Whenever you touch, it will burn immediately. Similarly, if you think of Kṛṣṇa, the same example, touching fire. So Kṛṣṇa will purify you. Śṛṇvatāṁ sva-kathāḥ kṛṣṇaḥ puṇya-śravaṇa-kīrtanaḥ (SB 1.2.17). Just like you are being purified by hearing about Kṛṣṇa daily. Otherwise, why you are coming here? We have no money to bribe you to come here. You are feeling, becoming Kṛṣṇa-ized; therefore you are coming.
So this is the process, simple process. You simply be engaged in Kṛṣṇa consciousness. Then you become Kṛṣṇa-ized, purified. And as soon as you become purified, you understand Kṛṣṇa. Sevonmukhe hi jihvādau svayam (Brs. 1.2.234). "You understand Kṛṣṇa" means Kṛṣṇa becomes revealed. Just like something is covered, you try to move the covering, you see the goal. Similarly, by your constant endeavor to become Kṛṣṇa conscious, Kṛṣṇa will reveal to you, "Yes. You are so anxious to see Me? Here I am. Here I am. Yes." You will see Kṛṣṇa. So how this is possible? Premāñjana-cchurita-bhakti-vilocanena santaḥ sadaiva hṛdayeṣu vilokayanti (Bs. 5.38). By thinking of Kṛṣṇa, naturally you become attached.
(Srila Prabhupada Lecture, Los Angeles, December 31, 1973)