Next, one may raise the question of how one goes about approaching that abode of the Supreme Lord. Information of this is given in the Eighth Chapter of the Bhagavad-gita. It is said there:
And whoever, at the time of death, quits his body, remembering Me alone, at once attains My nature. Of this there is no doubt.
Whatever state of being one remembers when he quits his body, that state he will attain without fail.
Therefore, Arjuna, you should always think of Me in the form of Kṛṣṇa and at the same time carry out your prescribed duty of fighting. With your activities dedicated to Me and your mind and intelligence fixed on Me, you will attain Me without doubt.
…This instruction to Arjuna is very important for all men engaged in material activities. The Lord does not say that one should give up his prescribed duties or engagements. One can continue them and at the same time think of Kṛṣṇa by chanting Hare Kṛṣṇa. This will free one from material contamination and engage the mind and intelligence in Kṛṣṇa. By chanting Kṛṣṇa’s names, one will be transferred to the supreme planet, Kṛṣṇaloka, without a doubt.
anta-kāle ca mām eva smaran muktvā kalevaram
yaḥ prayāti sa mad-bhāvam yāti nāsty atra saṁśayaḥ
“Anyone who quits his body, at the end of life, remembering Me, attains immediately to My nature; and there is no doubt of this.” (Bg. 8.5) One who thinks of Kṛṣṇa at the time of his death goes to Kṛṣṇa. One must remember the form of Kṛṣṇa; if he quits his body thinking of this form, he approaches the spiritual kingdom. Mad-bhāvaṁ refers to the supreme nature of the Supreme Being. The Supreme Being is sac-cid-ānanda-vigraha-eternal, full of knowledge and bliss. Our present body is not sac-cid-ānanda. It is asat, not sat. It is not eternal; it is perishable. It is not cit, full of knowledge, but it is full of ignorance. We have no knowledge of the spiritual kingdom, nor do we even have perfect knowledge of this material world where there are so many things unknown to us. The body is also nirānanda; instead of being full of bliss it is full of misery. All of the miseries we experience in the material world arise from the body, but one who leaves this body thinking of the Supreme Personality of Godhead at once attains a sac-cid-ānanda body, as is promised in this fifth verse of the Eighth Chapter where Lord Kṛṣṇa says, “He attains My nature.”
The process of quitting this body and getting another body in the material world is also organized. A man dies after it has been decided what form of body he will have in the next life. Higher authorities, not the living entity himself, make this decision. According to our activities in this life, we either rise or sink. This life is a preparation for the next life. If we can prepare, therefore, in this life to get promotion to the kingdom of God, then surely, after quitting this material body, we will attain a spiritual body just like the Lord.
As explained before, there are different kinds of transcendentalists, the brahmavādi paramātmāvādi and the devotee, and, as mentioned, in the brahmajyoti (spiritual sky) there are innumerable spiritual planets. The number of these planets is far, far greater than all of the planets of this material world. This material world has been approximated as only one quarter of the creation. In this material segment there are millions and billions of universes with trillions of planets and suns, stars and moons. But this whole material creation is only a fragment of the total creation. Most of the creation is in the spiritual sky. One who desires to merge into the existence of the Supreme Brahman is at once transferred to the brahmajyoti of the Supreme Lord and thus attains the spiritual sky. The devotee, who wants to enjoy the association of the Lord, enters into the Vaikuṇṭha planets, which are innumerable, and the Supreme Lord by His plenary expansions as Nārāyaṇa with four hands and with different names like Pradyumna, Aniruddha, Govinda, etc., associates with him there. Therefore at the end of life the transcendentalists either think of the brahmajyoti, the Paramātmā or the Supreme Personality of Godhead Śrī Kṛṣṇa. In all cases they enter into the spiritual sky, but only the devotee, or he who is in personal touch with the Supreme Lord, enters into the Vaikuṇṭha planets. The Lord further adds that of this “there is no doubt.” This must be believed firmly. We should not reject that which does not tally with our imagination; our attitude should be that of Arjuna: “I believe everything that You have said.” Therefore when the Lord says that at the time of death whoever thinks of Him as Brahman or Paramātmā or as the Personality of Godhead certainly enters into the spiritual sky, there is no doubt about it. There is no question of disbelieving it. (from Introduction to the Bhagavad-gita As It Is )
Bhagavad-gita As It Is 1972 Edition
By His Divine Grace A.C. Bhaktivedanta Swami Prabhupada
Chapter 8, Text 5-7
Attaining the Supreme
anta-kāle ca mām eva
smaran muktvā kalevaram
yaḥ prayāti sa mad-bhāvaṁ
yāti nāsty atra saṁśayaḥ
anta-kāle—at the end of life; ca—also; mām—unto Me; eva—certainly; smaran—remembering; muktvā—quitting; kalevaram—the body; yaḥ—he who; prayāti—goes; saḥ—he; mad-bhāvam—My nature; yati—achieves; na—not; asti—there is; atra—here; saṁśayaḥ—doubt.
And whoever, at the time of death, quits his body, remembering Me alone, at once attains My nature. Of this there is no doubt.
Purport
In this verse the importance of Kṛṣṇa consciousness is stressed. Anyone who quits his body in Kṛṣṇa consciousness is at once transferred to the transcendental abode of the Supreme Lord. The word smaran (remembering) is important. Remembrance of Kṛṣṇa is not possible for the impure soul who has not practiced Kṛṣṇa consciousness in devotional service. To remember Kṛṣṇa one should chant the mahāmantra, Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare, incessantly, following in the footsteps of Lord Caitanya, being more tolerant than the tree, humbler than the grass and offering all respect to others without requiring respect in return. In such a way one will be able to depart from the body successfully remembering Kṛṣṇa and so attain the supreme goal.
yaṁ yaṁ vāpi smaran bhāvaṁ
tyajaty ante kalevaram
taṁ tam evaiti kaunteya
sadā tad-bhāva-bhāvitaḥ
yam yam—whatever; vā—either; api—also; smaran—remembering; bhāvam—nature; tyajati—give up; ante—at the end; kalevaram—this body; tam tam—similar; eva—certainly; eti—gets; kaunteya—O son of Kuntī; sadā—always; tat—that; bhāva—state of being; bhāvitaḥ—remembering.
Whatever state of being one remembers when he quits his body, that state he will attain without fail.
Purport
The process of changing one’s nature at the critical moment of death is here explained. How can one die in the proper state of mind? Mahārāja Bharata thought of a deer at the time of death and so was transferred to that form of life. However, as a deer, Mahārāja Bharata could remember his past activities. Of course the cumulative effect of the thoughts and actions of one’s life influences one’s thoughts at the moment of death; therefore the actions of this life determine one’s future state of being. If one is transcendentally absorbed in Kṛṣṇa’s service,then his next body will be transcendental (spiritual), not physical. Therefore the chanting of Hare Kṛṣṇa is the best process for successfully changing one’s state of being to transcendental life.
tasmāt sarveṣu kāleṣu
mām anusmara yudhya ca
mayy arpita-mano-buddhir
mām evaiṣyasy asaṁśayaḥ
tasmāt—therefore; sarveṣu—always; kāleṣu—time; mām—unto Me; anusmara—go on remembering; yudhya—fight; ca—also; mayi—unto Me; arpita—surrender; manaḥ—mind; buddhiḥ—intellect; mām—unto Me; eva—surely; eṣyasi—will attain; asaṁśayaḥ—beyond a doubt.
Therefore, Arjuna, you should always think of Me in the form of Kṛṣṇa and at the same time carry out your prescribed duty of fighting. With your activities dedicated to Me and your mind and intelligence fixed on Me, you will attain Me without doubt.
Purport
This instruction to Arjuna is very important for all men engaged in material activities. The Lord does not say that one should give up his prescribed duties or engagements. One can continue them and at the same time think of Kṛṣṇa by chanting Hare Kṛṣṇa. This will free one from material contamination and engage the mind and intelligence in Kṛṣṇa. By chanting Kṛṣṇa’s names, one will be transferred to the supreme planet, Kṛṣṇaloka, without a doubt.