Sri Krishna is the Supreme Personality of Godhead. It is stated in the Svetasvatara Upanishad (6.8) "The Supreme Lord has multipotencies, which act so perfectly that all consciousness, strength and activity are being directed solely by His will". The material world, where we are now living, is called bahir-anga-sakti, the external energy of Krishna. Krishna explains in the Bhagavad-Gita (9.10): "Under My superintendence the material energy is working". Apart from the material, external energy, there is another energy - the internal energy. By the internal energy the spiritual world is being manifested. As the material world is manipulated under the external energy, the spiritual world is conducted by the internal potency. That internal potency, called the Hladini Sakti, is Srimati Radharani.
In CC Adi 1.5 it is said "The loving affairs of Sri Radha and Krishna are transcendental manifestations of the Lord's internal pleasure-giving potency. Although Radha and Krishna are one in Their identity, They separated Themselves eternally". Srimati Radharani, as the highest devotee of Sri Krishna, derives the greatest pleasure in serving Him. She is the origin of all the Gopis and of all the Goddesses of Fortune (Lakshmi devi) who are engaged in the service of the Lord. She is the mainstay, the ideal and the ultimate refuge of all devotees embarking on the path of devotional service. Without first getting the mercy of Srimati Radharani it is impossible to even approach Sri Krishna.
The Hare Krishna maha-mantra is in fact a prayer to Srimati Radharani. The word 'Hare' is derived from 'Hara' which denotes the internal energy or Hladini Sakti of Krishna. This is none other that Srimati Radharani. When one is chanting the maha-mantra, one is saying: "O Krishna ! O Radha !! Please engage me in your devotional service". Krishna is difficult to approach directly, but He is bhakta-vatsala, always eager to please His devotees. Thus the mood of a devotee is to invoke the compassion of Srimati Radharani Who then recommends the devotee to Sri Krishna. Since Krishna is easily pleased by Srimati Radharani, He then readily accepts the devotee in His service.
Vrindavan Lila
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When the Lord descends, He is invariably accompanied by His loving associates. Five thousand years when Sri Krishna descended in His original form, as a cowherd boy in Vrindavan, Srimati Radharani accompanied Him in Her original form. She appeared exactly two weeks after the appearance of Sri Krishna on the eighth day of the waning moon (ashtami). Srimati Radharani was found on a lotus flower by Vrashabhanu and his wife Kirtida near the village of Barsana, a few miles away from Nandagrama. It is said that Srimati Radharani first opened Her eyes only when Sri Krishna appeared before Her. Until that time Her eyes were closed.
Understanding the mellows of the relationship between Krishna and Radha is impossible from the mundane perspective. Understanding madhurya-rasa (devotion at the platform of intimacy), which is the highest level of relationship of a devotee with Krishna, is only possible in the most elevated stages of bhakti where there is not even a tinge of material contamination. Therefore Svarupa Damodara Gosvami has written: "The loving affairs of Radha and Krishna are not ordinary, material loving affairs, although they appear like that. Rascals and fools misunderstand Krishna to be an ordinary man. They do not know Krishna's transcendental nature. They try to imitate Krishna's rasa-lila, His dancing with the Gopis". There is no offense greater than this. Devotees starting on the path of bhakti must carefully avoid such offenses. They must simply pray to Srimati Radharani, as their most compassionate Mother, for mercy, for bhakti and for an opportunity to serve Sri Krishna.
Qualities of Srimati Radharani
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As explained in Bhakti-rasamrta-sindhu (Nectar of Devotion), Krishna possesses sixty-four transcendental qualities. Srimati Radharani has twenty-five transcendental qualities, but She can control even Krishna by them. Her transcendental qualities are as follows: (1) She is sweetness personified; (2) She is a fresh young girl; (3) Her eyes are always moving; (4) She is always brightly smiling; (5) She possesses all auspicious marks on Her body; (6) She can agitate Krishna by the flavor of Her person; (7) She is expert in the art of singing; (8) She can speak very nicely and sweetly; (9) She is expert in presenting feminine attractions; (10) She is modest and gentle; (11) She is always very merciful; (12) She is transcendentally cunning; (13) She knows how to dress nicely; (14) She is always shy; (15) She is always respectful; (16) She is always patient; (17) She is very grave; (18) She is enjoyed by Krishna; (19) She is always situated on the highest devotional platform; (20) She is the abode of love of the residents of Gokula; (21) She can give shelter to all kinds of devotees; (22) She is always affectionate to superiors and inferiors; (23) She is always obliged by the dealings of Her associates, (24) She is the greatest amongst Krishna's girl friends; (25) She always keeps Krishna under Her control.
Krishna means 'all attractive', since He attracts every one to Him. But Srimati Radharani attracts even Krishna. Although Krishna says vedaham samatitani - "I know everything" - He fails to understand Radharani. Krishna is acyuta (inconceivable), but for Him Radharani is inconceivable. Radharani is so great. Krishna thought, "I am full. I am complete in every respect, but still I want to understand Radharani." This question obliged Krishna to accept the propensities of Radharani to understand Himself. So five hundred years ago Krishna appeared as Caitanya Mahaprabhu, in the mood of Srimati Radharani and with Her golden complexion, as His own greatest devotee. Krishna did this to understand the depth of devotion of Srimati Radharani.
Mercy of Srimati Radharani
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Srimati Radharani is the ideal maha-bhagvat. As the greatest devotee, She is also the most compassionate. She is unable to bear the suffering of the souls trapped in the material world. The word "aradhaya" (prayers) is derived from "Radha" and means "worshippable". Similarly the word "aparadha" (offenses) means "against Radha". When one performs devotional service, one is pleasing Srimati Radharani and when commits Vaishnava aparadha against Krishna or His devotees, one is offending Radharani. Srimati Radharani is the guardian, the mentor and the benefactor of all aspiring devotees. When a soul starts to inquire about Krishna, Srimati Radharani is most pleased and takes charge of his devotional advancements. As one makes progress, one continues to invoke the mercy of Srimati Radharani and when She is pleased, Krishna is automatically pleased.
All glories to Srimati Radharani !!