Why is rice not eaten on Ekādaśī?

Ekādaśī is Viṣṇu’s day of fasting, and tradition asks even non-fasting family members to avoid rice and other grains on it.

Ekādaśī, the eleventh day of each lunar fortnight, is dedicated to Viṣṇu. The defining rule of the vrata is giving up grains — rice, wheat, pulses — and rice is mentioned most because it is the staple in so much of India. Many households that do not otherwise fast still skip rice that day as a mark of respect for Viṣṇu.

The Purāṇic explanation is told as a story: on Ekādaśī, tradition says, sin takes shelter in grain, so avoiding grain is a way of keeping the day pure. Others give a simpler reason — a lighter diet helps the mind turn towards prayer, japa and the Viṣṇu Sahasranāma.

What is eaten instead: fruits, milk, nuts, potatoes, sābūdānā, kuṭṭū or rājgirā flour, according to family custom. The fast is broken on Dvādaśī morning, often with a little rice offered to Viṣṇu first.

Source: Ekādaśī-māhātmya in the Purāṇas; Vaiṣṇava practice · Fast is broken on Dvādaśī (pāraṇa)

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