Why do we fast on Ekādaśī?

Ekādaśī, the eleventh lunar day, is sacred to Viṣṇu; fasting from grains that day is a twice-monthly offering of self-restraint and remembrance.

Ekādaśī falls twice a month, on the eleventh day of the waxing and waning moon. It is the most widely kept vrata in Vaiṣṇava homes. The heart of the observance is not hunger itself but turning the mind to Viṣṇu: less attention to food, more to prayer, kīrtana and reading.

The common rule is to avoid grains and pulses (rice, wheat, dāl) and to eat fruit, milk and permitted foods, or to fast fully if one is able. The fast is broken the next morning (Dvādaśī) within the prescribed time, called pāraṇa, usually after offering food to God.

There are 24 Ekādaśīs in a year (26 in a year with an extra month), each with its own name and story. Start with what you can manage — even one meal of fruit with prayer is a true Ekādaśī.

Tradition, as told in the Padma Purāṇa, says that when Viṣṇu rested after a long battle, the demon Mura came to attack him. A radiant goddess emerged from Viṣṇu’s body and destroyed Mura. Pleased, Viṣṇu named her Ekādaśī and blessed all who would honour her day with fasting.

Source: Padma Purāṇa; Vaiṣṇava vrata tradition · Pāraṇa: breaking the fast on Dvādaśī

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