What are the rules of Chhaṭh Pūjā over its four days?

Nahāy-Khāy, Kharnā, evening arghya to the setting Sun and morning arghya to the rising Sun, with strict purity and a roughly 36-hour nirjalā fast.

Chhaṭh honours Sūrya and Chhaṭhī Maiyā, mainly in Bihar, Jharkhand, eastern UP and Nepal, and now wherever their families live. The main one falls on Kārtika śukla ṣaṣṭhī; a smaller Caitī Chhaṭh comes in spring.

Day 1, Nahāy-Khāy: bath, house cleaned, a sāttvic meal of kaddū-bhāt and chana dal cooked in ghee. Day 2, Kharnā: fasting all day, then gur-kheer and roṭī offered at night and eaten as prasāda; the nirjalā fast begins after this. Day 3: standing in water at a river or pond, the vratī offers arghya to the setting Sun with soop baskets of ṭhekuā, fruits and sugarcane. Day 4: arghya to the rising Sun, then pāraṇa.

Rules: no onion, garlic or non-veg in the house; prasāda made on a new or clean stove, often of clay; no tasting while cooking; cleanliness throughout. Family members help the vratī, and anyone may take a vow to assist.

Kārtika śukla ṣaṣṭhī (and Caitī Chhaṭh in spring) · Source: Bihar–Pūrvāñcal family tradition

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