When one became two and then one again , the mysterious trancendental circumstances of Radha Krishna and Their ever expanding love and attraction for each other, the very origins of loving affairs of which a temporary miniscule portion can be reflected in this life for a few short years . Sri Caitanya Mahāprabhu comes to demonstrate and glorify the power , beauty and purity of the Love of Srimati Radharani and Radharani reveals the original trancendental cupid who dances like a billion cupids within the groves of the trysting ground of Vraj, the trancendental abode of Vraja Raja Krishna.
Everything is explained by the Gaudia Vaisnava acaryas in their litratures beginning with Srila Rupa Goswami and Srila Ragganatha das Goswami , who were personally taught by Sri Caitanya Mahaprabhu.

Caitanya Caratamrita Ādi 1.5

rādhā kṛṣṇa-praṇaya-vikṛtir hlādinī śaktir asmād
ekātmānāv api bhuvi purā deha-bhedaṁ gatau tau
caitanyākhyaṁ prakaṭam adhunā tad-dvayaṁ caikyam āptaṁ
rādhā-bhāva-dyuti-suvalitaṁ naumi kṛṣṇa-svarūpam

Translation
The loving affairs of Śrī Rādhā and Kṛṣṇa are transcendental manifestations of the Lord’s internal pleasure-giving potency. Although Rādhā and Kṛṣṇa are one in Their identity, previously They separated Themselves. Now these two transcendental identities have again united, in the form of Śrī Kṛṣṇa Caitanya. I bow down to Him, who has manifested Himself with the sentiment and complexion of Śrīmatī Rādhārāṇī although He is Kṛṣṇa Himself..

The books of Srila AC Bhaktivedanta Swami Prabhupada have brought all these trancendental treasures all over the world .
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