The Hindu religious calendar is based on the lunar calendar, which divides the year into twelve lunar months, each split evenly into "dark" (waning) and "bright" (waxing) halves.
The eleventh day of the lunar month, in both the waning and waxing halves, is known as Ekadashi.
During each half of the lunar cycle, some days are designated as holy to certain gods and goddesses, and these are days for special worship.
The deity Vishnu considers the ekadashi, or eleventh day, of each lunar month to be holy.
With the exception of one, each of the twenty-four ekadashis has its own name, charter story, mandated ceremonies, and expected outcome.
Each of these twenty-four festival days is observed by pious Vaishnavas.
The ekadashis are:
- Papamochani Ekadashi and Kamada Ekadashi during Chaitra,
- Baruthani Ekadashi and Mohini Ekadashi during Baisakh,
- Achala Ekadashi and Nirjala Ekadashi during Jyeshth,
- Yogini Ekadashi and Devshayani Ekadashi during Ashadh,
- Kamika Ekadashi and Putrada Ekadashi during Kamika
- During the lunar month of Bhadrapada, Aja Ekadashi and Parivartini Ekadashi,
- Indira Ekadashi and Papankusha Ekadashi,
- Rambha Ekadashi and Devotthayan Ekadashi,
- Utpanna Ekadashi and Mokshada Ekadashi,
- Paush Ekadashi and Putrada Ekadashi,
- Magh Ekadashi and Vijaya Ekad
Some of these ekadashis are more significant to the general public than others, notably the Devshayani and Devotthayan Ekadashis, which commemorate Vishnu's "sleep" during the chaturmas period during the rainy season.
Putrada ("son-giving") Ekadashi is the only ekadashi that appears twice.
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