What is Pradoṣa vrata?

a Śiva vrata on the thirteenth lunar day (Trayodaśī), with worship at twilight — the pradoṣa time.

Pradoṣa is the twilight period around sunset, roughly from an hour and a half before to a little after. When it falls on Trayodaśī, the thirteenth day of either fortnight, it is especially sacred to Śiva. So Pradoṣa vrata comes twice a month.

Devotees fast during the day (or take one light meal), and at twilight bathe again and worship Śiva with water or milk abhiṣeka, bilva leaves, a lamp and the chant “Om Namaḥ Śivāya”. In South Indian temples, Nandī is bathed and worshipped at this hour. A Pradoṣa falling on Monday is called Soma Pradoṣa and on Saturday Śani Pradoṣa; both are considered especially auspicious.

Tradition holds that at pradoṣa time Śiva dances in joy, and that prayers at this hour are heard quickly. Check the exact date and twilight time for your city.

Trayodaśī twilight, twice a month · Source: Purāṇic Śaiva tradition

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