Some of the gopīs were factually detained from going to Kṛṣṇa by their husbands and were locked up by force within their rooms. Being unable to go to Kṛṣṇa, they began to meditate upon His transcendental form by closing their eyes. They already had the form of Kṛṣṇa within their minds. They proved to be the greatest yogīs; as is stated in the Bhagavad-gītā, a person who is constantly thinking of Kṛṣṇa within his heart with faith and love is considered to be the topmost of all yogīs. Actually, a yogī concentrates his mind on the form of Lord Viṣṇu. That is real yoga. Kṛṣṇa is the original form of all viṣṇu-tattvas. The gopīs could not go to Kṛṣṇa personally, so they began to meditate on Him as perfect yogīs.
In the conditioned stage of the living entities, there are two kinds of results of fruitive activities: the conditioned living entity who is constantly engaged in sinful activities has suffering as his result, and he who is engaged in pious activities has material enjoyment as a result. In either case—material suffering or material enjoyment—the sufferer or enjoyer is conditioned by material nature.
The gopī associates of Kṛṣṇa who assembled in the place where Kṛṣṇa was appearing were from different groups. Most of the gopīs were eternal companions of Kṛṣṇa. As stated in the Brahma-saṁhitā, ānanda-cin-maya-rasa-pratibhāvitābhiḥ: in the spiritual world the associates of Kṛṣṇa, especially the gopīs, are manifestations of the pleasure potency of Lord Kṛṣṇa. They are expansions of Śrīmatī Rādhārāṇī. But when Kṛṣṇa exhibits His transcendental pastimes within the material world in some of the universes, not only the eternal associates of Kṛṣṇa come but also those who are being promoted to that status from this material world. So some of the gopīs who joined Kṛṣṇa’s pastimes within this material world were coming from the status of ordinary human beings. If they had been bound by fruitive action, they were fully freed from the reaction of karma by constant meditation on Kṛṣṇa. Their severely painful yearnings caused by their not being able to see Kṛṣṇa freed them from all sinful reactions, and their ecstasy of transcendental love for Kṛṣṇa in His absence ended all their reactions to material pious activities. The conditioned soul is subjected to birth and death, either by pious or sinful activities, but the gopīs who began to meditate on Kṛṣṇa transcended both positions and became purified and thus elevated to the status of the gopīs already expanded by His pleasure potency. All the gopīs who concentrated their minds on Kṛṣṇa in the spirit of paramour love became fully purified of all the fruitive reactions of material nature, and some of them immediately gave up their material bodies developed under the three modes of material nature.
Mahārāja Parīkṣit heard Śukadeva Gosvāmī explain the situation of the gopīs who assembled with Kṛṣṇa in the rāsa dance. When he heard that some of the gopīs, simply by concentrating on Kṛṣṇa as their paramour, became freed from all contamination of material birth and death, he said, “The gopīs did not know that Kṛṣṇa is the Supreme Personality of Godhead. They accepted Him as a beautiful boy and considered Him to be their paramour. So how was it possible for them to get freed from the material condition just by thinking of a paramour?” One should consider here that Kṛṣṇa and ordinary living beings are qualitatively one. The ordinary living beings, being part and parcel of Kṛṣṇa, are also Brahman, but Kṛṣṇa is the Supreme—Parabrahman. The question is, If it is possible for a devotee to get free from the material, contaminated stage simply by thinking of Kṛṣṇa, then why should this not be possible for others who are also thinking of someone? If one is thinking of a husband or son, or if anyone at all is thinking of another living entity, then, since all living entities are also Brahman, why are all those who thus think of others not freed from the contaminated stage of material nature? This is a very intelligent question, because there are always atheists imitating Kṛṣṇa. In these days of Kali-yuga, there are many rascals who think themselves to be as good as Kṛṣṇa and who cheat people into believing that thinking of them is as good as thinking of Lord Kṛṣṇa. Parīkṣit Mahārāja, apprehending the future dangerous condition of blind followers of demoniac imitators, therefore asked this question, and fortunately it is recorded in Śrīmad-Bhāgavatam to warn innocent people that thinking of an ordinary man and thinking of Kṛṣṇa are not the same.