Sayana Ekadashi (Devasayana Ekadashi) occurs during the Shukla Paksha of Ashadha month. This auspicious day marks the beginning of Chaturmasya, the sacred four-month period during which Lord Vishnu rests in the milk ocean on His snake carrier, Ananta Shesha. Devotees observe strict vows of fasting and spiritual practices during these four months.
In ancient times, there was a glorious and righteous king named Mandhata, whose kingdom suffered from a catastrophic three-year drought. The crops failed, and the citizens faced devastating famine. Grieved by his subjects' misery, King Mandhata set out to the forest to find a solution from the great sages.
He reached the ashram of the wise Sage Angira, who explained to him that the drought was a result of some minor religious imbalance in the kingdom. The sage instructed the king that the absolute solution was for him and all his citizens to strictly observe the upcoming Sayana Ekadashi of Ashadha month.
Following the sage's advice, the king and his subjects observed the fast with complete faith and performed prayers to Lord Vishnu. Miraculously, heavy rain began to fall across the kingdom, filling the lakes and reviving the parched lands. The crops grew abundantly, restoring peace and prosperity. Thus, Sayana Ekadashi is celebrated as the auspicious gateway to divine rains and spiritual rejuvenation.