Shayani Ekadashi or Ashadi Ekadashi is an auspicious eleventh lunar day of the bright fortnight (Shukla paksha) of the Hindu month of Ashadha (June – July). This transcendental day is significant to Vaishnavas, followers of the Hindu God, Lord Vishnu. It is also known as Padma, Hari Shayani or Devpodhi.
After Ekadashi, Lord Vishnu goes into a deep state of meditation (Yoga Nidra) for four months or Chaturmas with all the Devas (demigods) and wakes up only on Prabodhini Ekadashi. It is said that after this day one should not perform any new auspicious ceremonies until Devotthano Ekadashi, which occurs during the month of Kartika (October-November), because the devas, being asleep cannot be invited to the sacrificial arena and because the Sun is travelling along its Southern course (Dakshinayanam).
Lord Vishnu’s deep meditation should not be taken in the literal sense but to be seen in the sense of spirituality. Lord Vishnu goes to Kshirasagara (cosmic/ divine/milky ocean) and meditates while resting on Shesha Naag.
Devotees worship Lord Vishnu and observe a day-long fast on Ekadashi. Consumption of food grains and lentils is strictly prohibited. Only fruits and roots can be consumed on this day. The fasting is broken on Dwadashi at a stipulated time.
Fasting on this Ekadashi purifies one of all sins and fulfills all ones desires. Therefore, whoever neglects to observe this sacred fast day is a good candidate for entering into hell.
Just to please the Supreme Lord Hrishikesha, the master of the senses, one should fast on this day.