The attitude of the gopis is like a mirror upon which the reflection of Krsna's beauty develops at every moment. Both Krsna and the gopis increase their transcendental beauty at every moment, and there is always transcendental competition between them.
No one can appreciate the beauty of Krsna by properly discharging his occupational duty or by undergoing austerities, practicing mystic yoga, cultivating knowledge or offering various kinds of prayers. Only those who are on the transcendental platform of love of God, who engage in devotional service only out of love, can appreciate the transcendental beauty of Krsna.
Such beauty is the essence of all opulences and is appreciated only in Goloka Vrndavana and nowhere else. In the form of Narayana the beauties of mercy, fame, etc., are all established by Krsna, but Krsna's gentleness and magnanimity do not exist in Narayana. They are found only in Krsna.
From Teachings of Lord Caitanya, ch.10: The Beauty of Krsna by Srila Prabhupada