yad imau loka-pālasya
putrau bhūtvā tamaḥ-plutau
na vivāsasam ātmānaṁ
ato ’rhataḥ sthāvaratāṁ
syātāṁ naivaṁ yathā punaḥ
smṛtiḥ syān mat-prasādena
vṛtte svarlokatāṁ bhūyo
yat—because; imau—these two young demigods; loka-pālasya—of the great demigod Kuvera; putrau—born as sons; bhūtvā—being so (they should not have become like that); tamaḥ-plutau—so absorbed in the mode of darkness; na—not; vivāsasam—without any dress, completely naked; ātmānam—their personal bodies; vijānītaḥ—could understand that they were naked; su-durmadau—because they were very much fallen due to false pride; ataḥ—therefore; arhataḥ—they deserve; sthāvaratām—immobility like that of a tree; syātām—they may become; na—not; evam—in this way; yathā—as; punaḥ—again; smṛtiḥ—remembrance; syāt—may continue; mat-prasādena—by my mercy; tatra api—over and above that; mat-anugrahāt—by my special favor; vāsudevasya—of the Supreme Personality of Godhead; sānnidhyam—the personal association, face to face; labdhvā—obtaining; divya-śarat-śate vṛtte—after the expiry of one hundred years by the measurement of the demigods; svarlokatām—the desire to live in the celestial world; bhūyaḥ—again; labdha-bhaktī—having revived their natural condition of devotional service; bhaviṣyataḥ—will become.
These two young men, Nalakūvara and Maṇigrīva, are by fortune the sons of the great demigod Kuvera, but because of false prestige and madness after drinking liquor, they are so fallen that they are naked but cannot understand that they are. Therefore, because they are living like trees (for trees are naked but are not conscious), these two young men should receive the bodies of trees. This will be proper punishment. Nonetheless, after they become trees and until they are released, by my mercy they will have remembrance of their past sinful activities. Moreover, by my special favor, after the expiry of one hundred years by the measurement of the demigods, they will be able to see the Supreme Personality of Godhead, Vāsudeva, face to face, and thus revive their real position as devotees.
A tree has no consciousness: when cut, it feels no pain. But Nārada Muni wanted the consciousness of Nalakūvara and Maṇigrīva to continue, so that even after being released from the life of trees, they would not forget the circumstances under which they had been punished. Therefore, to bestow upon them special favor, Nārada Muni arranged things in such a way that after being released, they would be able to see Kṛṣṇa in Vṛndāvana and thus revive their dormant bhakti.
Each day of the demigods in the upper planetary system equals six months of our measurement. Although the demigods in the upper planetary system are attached to material enjoyment, they are all devotees, and therefore they are called demigods. There are two kinds of persons, namely the devas and the asuras. Asuras forget their relationship with Kṛṣṇa (āsuraṁ bhāvam āśritāḥ), whereas the devas do not forget.
The distinction between a pure devotee and a karma-miśra devotee is this: a pure devotee does not desire anything for material enjoyment, whereas a mixed devotee becomes a devotee to become a first-class enjoyer of this material world. One who is in direct touch with the Supreme Personality of Godhead in devotional service remains pure, uncontaminated by material desires (anyābhilāṣitā-śūnyaṁ jñāna-karmādy-anāvṛtam [Bhakti-rasāmṛta-sindhu
“One should render transcendental loving service to the Supreme Lord Kṛṣṇa favorably and without desire for material profit or gain through fruitive activities or philosophical speculation. That is called pure devotional service.” Bhakti-rasāmṛta-sindhu 1.1.11
By karma-miśra-bhakti one is elevated to the celestial kingdom, by jñāna-miśra-bhakti one is able to merge in the Brahman effulgence, and by yoga-miśra-bhakti one is able to realize the omnipotency of the Supreme Personality of Godhead. But pure bhakti does not depend on karma, jñāna or yoga, for it simply consists of loving affairs. The liberation of the bhakta, therefore, which is called not just mukti but vimukti, surpasses the five other kinds of liberation—sāyujya, sārūpya, sālokya, sārṣṭi and sāmīpya. A pure devotee always engages in pure service (ānukūlyena kṛṣṇānuśīlanaṁ bhaktir uttamā). Taking birth in the upper planetary system as a demigod is a chance to become a further purified devotee and go back home, back to Godhead. Nārada Muni indirectly gave Maṇigrīva and Nalakūvara the greatest opportunity by his so-called curse.
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