Nanda Mahārāja returned to Vṛndāvana without Kṛṣṇa and Balarāma. He was accompanied only by the cowherd boys and men. It was certainly a very pathetic scene for the gopīs, mother Yaśodā, Śrīmatī Rādhārāṇī and all the other residents of Vṛndāvana. Many devotees have tried to make adjustments to Kṛṣṇa’s being away from Vṛndāvana because, according to expert opinion, Kṛṣṇa, the original Supreme Personality of Godhead, never goes even a step out of Vṛndāvana. He always remains there. The explanation of expert devotees is that Kṛṣṇa was actually not absent from Vṛndāvana; He came back with Nanda Mahārāja as promised.
When Kṛṣṇa was starting for Mathurā on the chariot driven by Akrūra and the gopīs were blocking the way, Kṛṣṇa assured them that He was coming back just after finishing His business in Mathurā. He told them not to be overwhelmed and in this way pacified them. But when He failed to come back with Nanda Mahārāja, it appeared that He either cheated them or could not keep His promise. Expert devotees, however, have decided that Kṛṣṇa was neither a cheater nor a breaker of promises. Kṛṣṇa, in His original identity, returned with Nanda Mahārāja and stayed with the gopīs and mother Yaśodā in His bhāva expansion. Kṛṣṇa and Balarāma remained in Mathurā not in Their original forms but in Their expansions as Vasudeva and Saṅkarṣaṇa. The real Kṛṣṇa and Balarāma were in Vṛndāvana in Their bhāva manifestation, whereas in Mathurā They appeared in the prabhava and vaibhava expansions. This is the expert opinion of advanced devotees of Kṛṣṇa. Externally, however, They were absent from Vṛndāvana. Therefore, when Nanda Mahārāja was preparing to return to Vṛndāvana, there was some discussion between him and the boys concerning how they could live in separation. The conclusion to separate was reached by mutual agreement.
Vasudeva and Devakī, who happened to be the real parents of Kṛṣṇa and Balarāma, wanted to keep Them now because of the death of Kaṁsa. While Kaṁsa was alive, Kṛṣṇa and Balarāma were kept under the protection of Nanda Mahārāja in Vṛndāvana. Now, naturally, the father and mother of Kṛṣṇa and Balarāma wanted Them to remain, specifically for the reformatory function of purification, the sacred thread ceremony. They also wanted to give Them a proper education, for this is the duty of the father. Another consideration was that all the friends of Kaṁsa outside Mathurā were planning to attack Mathurā. For that reason also Kṛṣṇa’s presence was required. Kṛṣṇa did not want Vṛndāvana disturbed by enemies like Dantavakra and Jarāsandha. If Kṛṣṇa were to go to Vṛndāvana, these enemies would not only attack Mathurā but would go on to Vṛndāvana, and the peaceful inhabitants of Vṛndāvana would be disturbed. Kṛṣṇa therefore decided to remain in Mathurā, and Nanda Mahārāja went back to Vṛndāvana. Although the inhabitants of Vṛndāvana felt separation from Kṛṣṇa, the resulting ecstasy (bhāva) caused them to perceive that Kṛṣṇa was always present with them by His līlā, or pastimes.
Since Kṛṣṇa had departed from Vṛndāvana and gone to Mathurā, the inhabitants of Vṛndāvana, especially mother Yaśodā, Nanda Mahārāja, Śrīmatī Rādhārāṇī, the gopīs and the cowherd boys, were simply thinking of Kṛṣṇa at every step. They were thinking, “Here Kṛṣṇa was playing in this way. Here Kṛṣṇa was blowing His flute. Kṛṣṇa was joking with us in this way, and Kṛṣṇa was embracing us like this.” This is called līlā-smaraṇa, and it is the process of association with Kṛṣṇa most recommended by great devotees; even Lord Caitanya, when He was at Purī, enjoyed līlā-smaraṇa association with Kṛṣṇa. Those in the most exalted position of devotional service and ecstasy can live with Kṛṣṇa always by remembering His pastimes. Śrīla Viśvanātha Cakravartī Ṭhākura has given us a transcendental literary work entitled Kṛṣṇa-bhāvanāmṛta, which is full with Kṛṣṇa’s pastimes. Exalted devotees can remain absorbed in Kṛṣṇa-thought by reading such books. Any book of kṛṣṇa-līlā, even this book, Kṛṣṇa, or our Teachings of Lord Caitanya, is actually solace for devotees feeling separation from Kṛṣṇa.
That Kṛṣṇa and Balarāma did not return to Vṛndāvana can be adjusted as follows: They did not break Their promise to return to Vṛndāvana, nor were They absent, but Their presence was necessary in Mathurā.