Air is within and without the body. Therefore when the external covering, the material body, is vanquished, the living spark, like the air within the body, continues to exist. And by the direction of the Lord, because He is the ultimate benefactor, the living entity is at once awarded the necessary spiritual body befitting his association with the Lord in the manner of sārūpya(equal bodily feature), sālokya (equal facility to live on the same planet with the Lord), sārṣṭi (equal possession of opulence like the Lord), and sāmīpya (equal association with the Lord).
(Srimad Bhagavatam------2:7:49-------purport).

Those who are associated with the Lord in the Vaikuṇṭha planets achieve all the bodily features of the Lord and appear to be the same as Lord Viṣṇu. Such liberation is called sārūpya-mukti, which is one of the five kinds of liberation. The devotees engaged in the transcendental loving service of the Lord never accept the sāyujya-mukti, or merging in the rays of the Lord called the brahma-jyotir. The devotees can achieve not only liberation but any success in the realm of religiosity, economic development or sense gratification up to the standard of the demigods in the heavenly planets. But such a pure devotee as Uddhava refuses to accept all such facilities. A pure devotee wants simply to engage in the service of the Lord and does not consider his own personal benefit.
(Srimad Bhagavatam------3:4:15-------purport).

The residents of Vaikuṇṭha, who are decorated with garlands and yellow silken garments, have four arms holding various weapons. Thus they conspicuously resemble Lord Viṣṇu. They have the same bodily features as Nārāyaṇa because they have attained the liberation of sārūpya, but they nevertheless act as servants. All the residents of Vaikuṇṭhaloka know perfectly well that their master is Nārāyaṇa, or Kṛṣṇa, and that they are all His servants. They are all self-realized souls who are nitya-mukta, everlastingly liberated. Although they could conceivably declare themselves Nārāyaṇa or Viṣṇu, they never do so; they always remain Kṛṣṇa conscious and serve the Lord faithfully. Such is the atmosphere of Vaikuṇṭhaloka. Similarly, one who learns the faithful service of Lord Kṛṣṇa through the Kṛṣṇa consciousness movement will always remain in Vaikuṇṭhaloka and have nothing to do with the material world.
(Srimad Bhagavatam------6:1:34-36-------purport).

He is always full in His spiritual potency, by which He shows equal mercy to the punishable and the protectable. The Lord is apāpa-viddham; He is never contaminated by the reactions of so-called sinful activities. When Kṛṣṇa was present on this earth, He killed many inimical nondevotees, but they all received sārūpya; in other words, they returned to their original spiritual bodies. One who does not know the Lord's position says that God is unkind to him but merciful to others. Actually the Lord says in Bhagavad-gītā (9.29), samo 'haṁ sarva-bhūteṣu na me dveṣyo 'sti na priyaḥ: "I am equal to everyone. No one is My enemy, and no one is My friend." But He also says, ye bhajanti tu māṁ bhaktyā mayi te teṣu cāpy aham: "If one becomes My devotee and fully surrenders unto Me, I give him special attention."
(Srimad Bhagavatam------6:9:35-------purport).

Pauṇḍraka, Narakāsura, Sālva and Kaṁsa were all inimical toward the Supreme Personality of Godhead, but because all these kings constantly thought of Him, they achieved the same liberation—sārūpya-mukti. The jñāna-bhakta, the devotee who follows the path of jñāna, also attains the same destination. If even the enemies of the Lord achieve salvation by constantly thinking about the Lord, what is to be said of pure devotees who always engage in the Lord's service and who think of nothing but the Lord in every activity?
(Srimad Bhagavatam------7:10:40-------purport).

Thus in spite of so much bodily strength, the elephant works as a menial servant for a human being. Agastya Muni thought it wise to curse the King to become an elephant because the powerful King did not receive Agastya Muni as one is obliged to receive a brāhmaṇa. Yet although Agastya Muni cursed Mahārāja Indradyumna to become an elephant, the curse was indirectly a benediction, for by undergoing one life as an elephant, Indradyumna Mahārāja ended the reactions for all the sins of his previous life. Immediately after the expiry of the elephant's life, he was promoted to Vaikuṇṭhaloka to become a personal associate of the Supreme Personality of Godhead, Nārāyaṇa, in a body exactly like that of the Lord. This is called sārūpya-mukti.
(Srimad Bhagavatam------8:4:10------purport).

When a devotee gets liberation, he becomes free from material contamination and engages as a servant of the Lord. This is explained in Śrīmad-Bhāgavatam (2.10.6): muktir hitvānyathā rūpaṁ svarūpena vyavasthitiḥ. The word svarūpa refers to sārūpya-mukti—going back home, back to Godhead, and remaining the Lord's eternal associate, having regained a spiritual body exactly resembling that of the Lord, with four hands, holding the śaṅkha, cakra, gadā and padma. The difference between the mukti of the impersonalist and that of the devotee is that the devotee is immediately appointed an eternal servant of the Lord, whereas the impersonalist, although merging in the effulgence of the brahma-jyotir, is still insecure and therefore generally falls again to this material world. Āruhya kṛcchreṇa paraṁ padaṁ tataḥ patanty adho 'nādṛta-yuṣmad-aṅghrayaḥ (S.B.10:2:32).
(Srimad Bhagavatam------8:4:13------purport).

But the liberation of those who are on the transcendental platform of love and affection is vimukti, special liberation. Thus the serpent first entered the body of Kṛṣṇa personally and mixed with the Brahman effulgence. This merging is called sāyujya-mukti. But from later verses we find that Aghāsura attained sārūpya-mukti. Text 38 explains that Aghāsura attained a body exactly like that of Viṣṇu, and the verse after that also clearly states that he attained a completely spiritual body like that of Nārāyaṇa. Therefore in two or three places the Bhāgavatam has confirmed that Aghāsura attained sārūpya-mukti. One may then argue, How is it that he mixed with the Brahman effulgence? The answer is that as Jaya and Vijaya, after three births, again attained sārūpya-mukti and association with the Lord, Aghāsura received a similar liberation.
(Srimad Bhagavatam------10:12:33------purport).

All the Viṣṇu forms had four arms, with conchshell and other articles, but these characteristics are also possessed by those who have attained sārūpya-mukti in Vaikuṇṭha and who consequently have forms exactly like the form of the Lord. However, these Viṣṇu forms appearing before Lord Brahmā also possessed the mark of Śrīvatsa and the Kaustubha gem, which are special characteristics possessed only by the Supreme Lord Himself. This proves that all these boys and calves were in fact directly expansions of Viṣṇu, the Personality of Godhead, not merely His associates of Vaikuṇṭha. Viṣṇu Himself is included within Kṛṣṇa. All the opulences of Viṣṇu are already present in Kṛṣṇa, and consequently for Kṛṣṇa to demonstrate so many Viṣṇu forms was actually not very astonishing.
(Srimad Bhagavatam------10:13:47------purport).