Each Form has a Purpose

Shri Shri Radha Govinda (Pratibhu Murti) at Vrindavan

The Govinda Deity is called the functional Deity because He shows us how to serve Radha and Krishna. The Madana-mohana Deity simply establishes that "I am Your eternal servant." With Govinda, however, there is actual acceptance of service. Govinda resides eternally in Vrindavana. In the spiritual world of Vrindavana the buildings are made of touchstone, the cows are known as surabhi cows, givers of abundant milk, and the trees are known as wish-fulfilling trees, for they yield whatever one desires. In Vrindavana Krishna herds the surabhi cows, and He is worshiped by hundreds and thousands of gopis, cowherd girls, who are all goddesses of fortune. When Krishna descends to the material world, this same Vrindavana descends with Him, just as an entourage accompanies an important personage. Because when Krishna comes His land also comes, Vrindavana is considered to exist beyond the material world. Therefore devotees take shelter of the Vrindavana in India, for it is considered to be a replica of the original Vrindavana. Although one may complain that no kalpa-vrksa, wish-fulfilling trees, exist there, when the Gosvamis were there, kalpa-vrksa were present. It is not that one can simply go to such a tree and make demands; one must first become a devotee. The Gosvamis would live under a tree for one night only, and the trees would satisfy all their desires. For the common man this may all seem very wonderful, but as one makes progress in devotional service, all this can be realized.
Vrindavana is actually experienced as it is by persons who have stopped trying to derive pleasure from material enjoyment. "When will my mind become cleansed of all hankering for material enjoyment so I will be able to see Vrindavana?" one great devotee asks. The more Krishna conscious we become and the more we advance, the more everything is revealed as spiritual. Thus Krishnadasa Kaviraja Gosvami considered the Vrindavana in India to be as good as the Vrindavana in the spiritual sky, and in the sixteenth verse of the Caitanya-caritamrta he describes Radharani and Krishna as seated beneath a wish-fulfilling tree in Vrindavana, on a throne decorated with valuable jewels. There Krishna's dear gopi friends serve Radha and Krishna by singing, dancing, offering betel nuts and refreshments, and decorating Their Lordships with flowers. Even today in India people decorate swinging thrones and re-create this scene during the month of July–August. Generally at that time people go to Vrindavana to offer their respects to the Deities there.

(Introduction, Shri Chaitanya-charitamrita)