The eleventh day (ekadashi) of the dark,
waxing half of the lunar month of Shravan (July–August) is the festival.
Kamika Ekadashi, like other eleventh-day observances, is
devoted to the worship of Vishnu.
Most Hindu holidays have mandated ceremonies, which
generally include fasting (upavasa) and devotion, and frequently promise
particular rewards if they are followed faithfully.
The word Kamika means "desiring," which is a notion
that the charter story supports.
According to legend, the brahmins of one hamlet refuse to
conduct religious ceremonies for a landowner who murdered another brahmin.
By observing the Kamika Ekadashi, the landowner is cleansed
of that sin and therefore allowed to have the necessary ceremonies conducted.
You may also want to read more about Hinduism here.
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