Bhima's confession
In the Kamyaka forest during the vanavasa of the Pandavas, on a burning summer noon, Bhimasena approached his grandfather Rishi Krishna-Dvaipayana Vyasa. His face was clouded with a sorrow the strongest man on earth is not accustomed to feel. He said: 'Pitamah, Yudhishthira, Arjuna, Nakula, Sahadeva — even mother Kunti and Draupadi — keep every Ekadashi of the year. Only I, whose hunger is such that I cannot go one prahara without food, break every vrat before it is half-done. Am I forever cut off from this greatest of all punya?'
Vyasa's smile
Vyasa Muni looked upon his mighty grandson with kindness, for he saw in that hunger not weakness but the very fire which Vayu-deva himself had placed in his son. He said: 'Bhima, hunger is the shakti of your body — do not curse it. The rishis of old, seeing that there would always be those like you, prescribed one Ekadashi that stands for all the twenty-four combined.' Bhima's face lifted for the first time in the tale.
The prescription
Vyasa continued: 'It is the Jyeshtha Shukla Ekadashi. But upon this one day the vrat is nirjala — not one drop of water may touch the lips from sunrise on Dashami until Dwadashi parana at the appointed brahma-muhurat. If you observe it with this severity, its punya equals ALL twenty-four Ekadashis of the year combined. One day of unbroken tapa, one year of merit — the shastra itself has weighed it so.'
Bhima's vrat under the Jyeshtha sun
Bhima bowed, took the sankalpa from Vyasa, and observed the vrat with the same fierce determination with which he had once vowed to break Duryodhana's thighs. Through the burning Jyeshtha sun, when the very stones cracked around him, he did not open his lips for water. Through the night, when his throat felt as though he had swallowed the sands of Kurukshetra, he sat chanting Vishnu Sahasranama in a low, steady voice. He nearly collapsed at midnight; his brothers stood by him weeping but did not touch him with even a drop, for that would break the vrat.
The parana and the naming
At Dwadashi brahma-muhurat, Draupadi placed in his palm a leaf of tulsi and a lota of Ganga jal. Bhima broke the fast, and the strength of a thousand elephants returned to him at once. The devas rained flowers upon the Kamyaka forest. Bhagwan Vishnu himself, it is said, appeared in a golden vimana and blessed Bhima: 'This vrat you have kept shall from today be called Bhimseni Ekadashi. Whoever, of any varna or ashrama, keeps it as you have kept it, shall have the punya of every Ekadashi of the year.'
"Grants the merit of ALL twenty-four Ekadashi vratas of the year. Prescribed for householders and busy karma-yogis who cannot observe every monthly Ekadashi. Even one lifetime observance of Nirjala with full nishtha is said to grant Vaikuntha at the end of life."