The eleventh day (ekadashi) of the bright
(waxing) half of the lunar month of Bhadrapada (August–September) is a
religious celebration.
This, like other eleventh-day observances, is devoted to
Vishnu devotion.
This day is dedicated to Vishnu's wife Lakshmi, the goddess
of riches and prosperity, and her husband Vishnu.
In her Mahalakshmi form (as recounted in the Devimahatmya),
she can destroy demons that the gods can't, and she can reclaim the kingdom
that the gods have lost.
Vishnu is said to be resting on the snake Shesha, in an
ocean of milk, with Lakshmi stroking his feet at this festival.
Parivartini means "turning," and Vishnu is said to
be turning in his slumber on this day.
See also cosmology and churning of the ocean.
You may also want to read more about Hinduism here.
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