The devotees of the Lord are full of compassion and mercy, and can never tolerate the suffering of the living entities. When they witness the ignorance in which the jivas are trapped, thinking pain to be pleasure and not endeavouring to cross over the ocean of birth and death, they contemplate of ways to deliver them from that miserable state of life. The great sage Narad, seeing the conditioned of the people in the age of Kali, felt great distress and decided to bestow mercy upon them. He considered the situation and reached the conclusion that only the Supreme Personality of Godhead Sri Krishna could rescue them from their pitiable condition. Being a very soft-hearted and magnanimous Vaishnava, he decided to bring Krishna to the rescue of the jivas, and thinking thus he proceeded towards Dwarak in the spiritual realm.
In Dwaraka, Sri Krishna, after having spent time with his dear wife Satyabhama, decided to go to the chamber of his most prominent queen, Devi Rukmini. When the news of the Lords imminent arrival was given to Rukmini, she immediately set about making preparations for the welcome of the Lord. Even though the palace was spotless clean, she herself started tidied everything and lit ghee lamps in all directions. She placed water pots at the entrance and decorated her chamber for the pleasure of her Lord. She then decorated herself and stood awaiting his arrival. When Sri Krishna came to her palace, she washed his lotus feet and offered him arati. Thereafter, considering his lotus feet to be her very life and soul, she placed them on her breasts and started shedding tears profusely. When Sri Krishna saw this, he was surprised and asked her what the matter was. He inquired whether he had committed a mistake or had failed to do something requested by her. Upon his questioning again and again, she told him that although he was the knower of all that is to be known, he was not aware of the love that his devotees feel for him. And therefore he would not be able to understand her feelings. She further said to him,”O my Lord! Your lotus feet are my very life and soul, and the pain which I feel when I think that you will leave my chambers soon is making me cry. Only Srimati Radhika can understand these feelings, for she is the topmost embodiment of love.” When Sri Krishna heard this, he was amazed to know that there was something which he did not comprehend and requested Rukmini to explain it to him further. Upon his request, she began explaining the love that the devotees feel for the Lord and the unlimited glories of his own two lotus feet. She then said that only when he would cultivate Radhabhav, the moods of Srimati Radhika, would he be able to understand her feelings. Hearing this Sri Krishna felt great jubilation in his heart and a desire to taste Radhabhav appeared in his heart.
Just then Narad Muni appeared there and was respectfully and affectionately welcomed by the Lord, who sat him on his throne and washed his lotus feet. He then enquired about the reason behind the sad expression on his face. To this Narad Muni answered, “My dear Lord, I am always engaged in singing your glories and spreading love of Godhead through out the universe. During my wanderings I came upon the jivas who are entrapped in the clutches of Maya and are being bitten by the snake of Kali. They are living in a miserable condition of life, thinking pain to be pleasure and being engrossed in satisfying their senses. They are so fallen that they are not able to take to the path of Bhakti even if I try very heard to give your holy names to them. My Lord, you must bestow your mercy upon them and appear on the earthly planet to reestablish dharma.” The desire of the devotees of the Lord is the desire of the Lord. He is always eager to fulfil the aspirations of his devotees. Hearing Narad Muni, and deciding to taste Radhabhav, Krishna decided to appear on this earthly planet in the form of Sachinandan Gaurahari. Thinking thus, he displayed his golden-complexioned transcendental form to Narad Muni and Rukmini devi, who were astonished to see this form of the Lord and felt greatly pleased in their hearts upon beholding Sri Chaitanya Mahaprabhu. He then declared that he would appear as a devotee in Nawadwip in the house of Jagannath Mishra from the womb of Sachi devi, and would freely distribute love of Godhead and the holy names, while relishing the moods of Srimati Radhika. Thus Sri Krishna appeared as Sri Sachinandan Gaurahari to deliver all the conditioned living entities and to taste Radhabhav.
This beautiful story has been narrated by Srila Lochan Das thakur in his book Sri Chaitanya Mangal, which is a treasure chest of the honey like sweet pastimes of Sri Chaitanya Mahaprabhu.