"Although the dealings of the gopīs with Kṛṣṇa are wrongly celebrated by many as lust, great sages and saintly persons like Uddhava hanker for such loving affairs with Kṛṣṇa." Śrīla Kṛṣṇadāsa Kavirāja, the author of Caitanya-caritāmṛta, has therefore said,
kāma, prema,-doṅhākāra vibhinna lakṣaṇa
lauha āra hema yaiche svarūpe vilakṣaṇa
"As there is a difference between iron and gold, so there is a difference between material lust and Kṛṣṇa's loving affairs with the gopīs" (CC.1:4:164). Although such loving affairs may sometimes resemble material lust, the difference is as follows:

ātmendriya-prīti-vāñchā-tāre bali 'kāma'
kṛṣṇendriya-prīti-icchā dhare 'prema' nāma
"The desire to satisfy one's own senses is called lust, while the desire to satisfy the senses of Kṛṣṇa is called prema, love of God" (CC.1:4:165).

(Narada Bhakti Sutra).

Lust and love have different characteristics, just as iron and gold have different natures.
One should try to discriminate between sexual love and pure love, for they belong to different categories, with a gulf of difference between them. They are as different from one another as iron is from gold.

(Sri Caitanya Caritamrta-------1:4:164-------purport).

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