Significance
Nirjala Ekadashi, in the bright fortnight of Jyeshtha, is considered the most austere and meritorious of all Ekadashis. "Nirjala" means without water -- the devotee fasts without consuming even a drop of water for the full 24 hours. The sage Bhima (of the Pandavas), who could not observe all 24 annual Ekadashis due to his enormous appetite, asked Vedavyasa for a single Ekadashi whose merit would equal all others combined. Vyasa prescribed Nirjala Ekadashi. Those who successfully complete this fast are said to receive the cumulative merit of all 24 Ekadashis.
Preparation
Rituals & Vidhi
Dashami Meal
On the day before (Dashami), eat a nourishing meal before sunset. Mentally resolve to observe the complete Nirjala fast.
Morning Vishnu Puja
Bathe at sunrise on Ekadashi and perform Vishnu puja. Offer Tulsi, yellow flowers, and incense. Pray for strength to complete the waterless fast.
Mantra: Om Namo Bhagavate Vasudevaya
All-Day Prayer
Spend the day in prayer, Vishnu Sahasranama recitation, Bhagavata reading, or kirtan. Avoid sleep during the day as prescribed in the Padma Purana.
Daan on Dwadashi
Break the fast on Dwadashi morning after sunrise within the parana window. Gift a water pot (Kalash), umbrella, and footwear to a Brahmin or a needy person as symbolic charity of the summer heat.
Fasting
This is the only Hindu fast where even water is traditionally forbidden for 24 hours. Those with health conditions should consult a doctor and may observe a modified fast with water only. The merit is in the intention and devotion, not just the physical austerity.
Family Guidance
Older children and teenagers can participate in a partial fast (fruits and water). Tell the story of Bhima and Vedavyasa. Use the day to discuss self-discipline and the power of the mind over the body.