Mohinii EkAdasii
In the Mahabharata there's a story of Dhrishthabuddhi that is told. Then there's a mention of the vrata called Vaisakh vrata that removes all sin. There it suggests to observe a fast by eating once per day after noon for one month (Mahabharata Anusasana parva, chapter 106.)

It also refers to Vaishakhsuklaikadasivrat known as Mohini and quotes Padma Purana as its origin Uttara Khanda chapter 51.



The Following is Mohinii EkAdasii: from the KUrma PurANa

Sri Yudhisthira Maharaja said, “Oh  JanArdana, what is the name of the EkAdasii that occurs during the light fortnight (sukla paksha) of the month of VaisAkha (April-May) ? What is the process for observing it properly? Kindly narrate all of these details to me.”

The Supreme Personality of Godhead, Lord Sri Krishna replied, “Oh blessed son of Dharma, what Vasishtha Muni once told to Lord Ramachandra I shall now describe to you. Please hear Me attentively.

“Lord Ramachandra asked Vasishtha Muni, ‘Oh great sage, I would like to hear about the best of all fasting days – that day which destroys all kinds of sins and sorrows. I have suffered long enough in separation from My dear SitA, and so I wish to hear from you about how My suffering can be ended.’

“The sage Vasishtha replied, ‘Oh Lord RAma, Oh You whose intelligence is so keen, simply by remembering Your name one can cross the ocean of the material world. You have questioned me in order to benefit all of humanity and fulfill everyone’s desires. I shall now describe that day of fasting which purifies the whole world.

“ ‘Oh Rama, that day is known as VaisAkha-sukla EkAdasii, which falls on DvAdasii. It removes all sins and is famous as Mohinii EkAdasii.NOTE
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“ ‘Truly, Oh dear Rama, the merit of this EkAdasii frees the fortunate soul who observes it from the network of illusion. Therefore, if You want to relieve Your suffering(s), observe this auspicious EkAdasii perfectly, for it removes all obstacles from one's’ path and relieves the greatest miseries. Kindly listen as I describe its glories, because for one who even just hears about this auspicious EkAdasii, the greatest sins are nullified.

“ ‘On the banks of the Sarasvati River there was once a beautiful city named BhadrAvati, which was ruled by King DyutimAn. Oh RAma, that steadfast, truthful, and highly intelligent king was born in the dynasty of the Moon (Chandra-vamsa). In his kingdom was a merchant named DhanapAla, who possessed a great deal of wealth of food grains and money. He was also very pious. DhanapAla arranged for lakes to be dug, sacrificial arenas to be erected, and beautiful gardens to be cultivated for the benefit of all the citizens of BhadrAvati. He was an excellent devotee of Lord Vishnu and had five sons: SumAna, DyutimAn, MedhAvii, Sukriti, and Dhrishthabuddhi.

“ ‘Unfortunately, his son Dhrishthabuddhi always engaged in greatly sinful activities, such as sleeping with prostitutes and associating with similar degraded persons. He enjoyed illicit sex, gambling, and many other varieties of acts aimed at gratifying the senses. He disrespected the demigods (devas), the brahmins, the forefathers and other elders of the community, as well as his family’s guests. The evil-hearted Dhrishthabuddhi spent up his father’s wealth indiscriminately, always feasting on untouchable foods and drinking alcohol to excess.

“ ‘One day DhanapAla kicked Dhrishthabuddhi out of the house after he saw him walking along the road arm-in-arm with a known prostitute. From then on all Dhrishthabuddhi’s relatives were highly critical of him and distanced themselves from him also. After he had sold all of his inherited ornaments and become destitute, the prostitute also abandoned him and insulted him because of his poverty.

“ ‘Dhrishthabuddhi was now full of anxiety, and also hungry. He thought, “What should I do ? Where should I go ? How can I maintain myself ? “ He then began to steal. The king’s constables arrested him, but when they learned who it was, and that his father was the famous DhanapAla, they released him. He was caught and released in this way many times. But at last, sick of his arrogance and total disrespect for others, and their property, the ill-mannered Dhrishthabuddhi was apprehended, handcuffed, and then beaten.  After whipping him, the king’s marshals warned him, “Oh evil minded one ! There is no place for you in this kingdom……….!!!”

“ ‘However, Dhrishthabuddhi was freed from his tribulation by his father and immediately thereafter entered the dense forest. He wandered here and there, hungry and thirsty and suffering greatly. Eventually he began killing the jungle animals, the lions, deer, boars, and even wolves for food. Always ready in his hand was his bow, always on his shoulder was his quiver full of arrows. He also killed many birds, such as chakoras, peacocks, kankas, doves and pigeons. He unhesitatingly slaughtered many species of birds and animals to maintain his sinful way of life, the sinful results accumulating more and more each day. On account of his previous sins, he was now immersed in an ocean of great sin that was so relentless that it appeared that he could not get out.

“ ‘Dhrishthabuddhi was always miserable and anxious, but one day, during the month of VaisAkha, by the force of some of his past merit he chanced upon the sacred Ashrama of KauNDinya Muni. The great sage had just finished bathing in the Ganges River, and water was dripping from him still. Dhrishthabuddhi had the great good fortune to touch some of those droplets of water that were falling from the great sage’s wet clothing. Instantly Dhrishthabuddhi was freed of his ignorance, and his sinful reactions were reduced. Offering his humble obeisances to KauNDinya Muni, Dhrishthabuddhi prayed to him with joined palms; ”Oh great brAhmana, please describe to me some of the atonement I may perform without too much endeavour. I have committed so many sins in my life, and these have now made me very poor.”

“ ‘The great rishi replied, “Oh son, listen with great attention, for by hearing me your life will change, and you will become free of all your remaining sins. In the light fortnight of this very month, VaisAkha (April-May) there occurs the sacred Mohinii EkAdasii, which has the power to nullify sins as vast and weighty as Mount Sumeru. If you follow my advice and faithfully observe a fast on this EkAdasii, which is so dear to Lord Hari, you will be freed from all the sinful reactions of many, many births.”

“ ‘Hearing these words with great joy, Dhrishthabuddhi promised to observe a fast on Mohinii EkAdasii according to the sage’s instructions and direction. Oh best of kings, Oh RAmachandra Bhagavan, by fasting completely on Mohinii EkAdasii, the once sinful Dhrishthabuddhi, the prodigal son of the merchant DhanapAla, became sinless. Afterwards he achieved a beautiful transcendental form and, free at last of all obstacles, rode upon the carrier of Lord Vishnu, Garuda, to the Supreme abode of the Lord.

“ ‘Oh RAmachandra, the fast day of Mohinii EkAdasii removes the darkest illusory attachments to material existence. There is thus no better fast day in all the three worlds than this.’ ”

Lord Sri Krishna concluded, “…and so, Oh Yudhishthira, there is no place of pilgrimage, no sacrifice, and no charity that can bestow merit equal to even one sixteenth of the merit a faithful devotee of Mine obtains by observing the Mohinii EkAdasii. And He who hears and studies the glories of Mohinii EkAdasii achieves the merit of giving away one thousand cows in charity.


Thus ends the narration of the glories of VaisAkha-sukla EkAdasii, or Mohinii EkAdasii, from the Kurma PurANa.

These stories have been summarised and slightly changed or abbreviated from how they are found in the celebrated book, "Ekadasi: The Day of Lord Hari" 1986. HH Krishna Balaram Swami. Bhaktivedanta Institute Press., Pages 77-81


(the above excerpt is used with permission)

The Ekadashi Book is now available in its entirety -free to download with our blessing at http://www.krsna.org
 
Entire book acknowledged to Mahamandelswar Mahant Krsna Balaram Swami

Dr. Vijay K. Parmar
European Secretary
Bhagavat Dharma Samaj



NOTE:

If the holy fast falls on DvAdasii, it is still called EkAdasii in the Vedik literature. Furthermore, in Garuda Purana (1:125.6), Lord BrahmA states to Narada Muni: “Oh brAhmana, this fast should be observed when there is a full EkAdasii, a mixture of EkAdasii and DwAdasii, or a mixture of three (EkAdasii, DwAdasii, and Trayodasii) but never on the day when there is a mixture of Dashami and EkAdasii.”

This is also upheld in the Hari Bhakti Vilas, Vaishnava smriti shastra, and upheld by Srila Bhaktisiddhanta Saraswati Thakura Prabhupad in his Navadwip Panjika introduction.



The Ekadasi Page:
Srila Bhaktisiddhanta Saraswati's Navadwip Panjika Intro'
Vaishnava Calendar Page
Ekadasi Vratas according to Hari Bhakti Vilas smriti
Ekadasis Throughout the year in detail - their observances, benefits, and individual origin
Choose The Month (Vaishnava or Western), Paksha or Ekadasi
No. Name of Ekadasis Vedik - Hindu Months Fortnights
K=Krishna paksha
S=Sukla paksha
Vaishnava Month Western Months
19 Utpanna Ekadasi Margashira - K Keshava Mase Nov-Dec
20 Mokshada Ekadasi (Vaikuntha ekadasi Sri Rangam) Margashira - S Keshava Mase Nov-Dec
21 Saphala Ekadasi Pausha - K Naaraayana Mase Dec-Jan
22 Putrada Ekadasi Pausha - S Naaraayana Mase Dec-Jan
23 Trisprisha Ekadasi Maagha - K Maadhava Mase Jan-Feb
24 Bhaimi Ekadasi Maagha - S Maadhava Mase Jan-Feb
25 Vijaya - Jaya Phaalguna - K Govinda Mase Feb-Mar
26 Amalaki Ekadasi Phaalguna - S Govinda Mase Feb-Mar
1 Paapavimochani Ekadasi Chaitra - K Vishnu Mase Mar-Apr
2 Kamaada - Damanakaaropani Ekadasi Chaitra - S Vishnu Mase Mar-Apr
3 Varuthini Ekadasi Vaisaakha - K Madhusudana Mase Apr-May
4 Mohini Ekadasi  Vaisaakha - S Madhusudana Mase Apr-May
5 Aparaa Ekadasi Jyeshtha - K Trivikrama Mase May-June
6 Pandava Nirjal Ekadasi Jyeshtha - S Trivikrama Mase May-June
7 Yogini Ekadasi Aashaadha - K Vaamana Mase June-July
8 Padma - Devasayani Ekadasi Aashaadha - S Vaamana Mase June-July
9 Kaamaika Ekadasi Shravana - K Sridhar Mase July-Aug
10 Putrada - Pavitraropani Ekadasi Shravana - S Sridhar Mase July-Aug
11 Ajaa - Annadaa Ekadasi Bhaadrapada - K Hrisikesha Mase Aug-Sept
12   Parivartini - Parshva Ekadasi Bhaadrapada - S Hrisikesha Mase Aug-Sept
13 Indiraa Ekadasi Aaswina - K Padmanabha Mase Sept-Oct
14 Paashaankusha Ekadasi Aaswina - S Padmanabha Mase Sept-Oct
15 Ramaa Ekadasi Kaarttika - K Damodara Mase Oct-Nov
16 Haribodhini (Probodhini) Devotthaani (Uttana) Ekadasi Kaarttika - S Damodara Mase Oct-Nov
17 Padmini - Vishuddha Ekadasi Adikamase Adikamase
18 Paramaa - Shuddha Ekadasi Adikamase Adikamase