Pōṣa-daśamī (Posh-dasami) vrat is a Jain festival that centers on the birth of Lord Parshvanath (the 23rd Tirthankar). It is observed by both Śvetāmbara and Digambara Jains, but the exact tithi can vary by local calendar (north Indian vs Gujarati calendars). In general, it falls on the 9th, 10th, and 11th days of the dark fortnight of the Poṣa month, and in the Gregorian calendar it often occurs in late December to early January, with the dates shifting each year.

What Jains usually do during Pōṣa-daśamī:

• Worship Parshvanath, often with a special lamp ritual using a lamp of many wicks (traditionally 108 wicks).
• Listen to sermons about Parshvanath’s life and virtues.
• Offer prayers and recite Navkar Mantra; perform reflection and meditation.
• Observe vows related to food and conduct, such as partial fasting or reduced meals for the days of the festival.
• Participate in temple rituals and sometimes street processions or temple-centered celebrations, depending on local customs.

Key point about practice across traditions:

• The core spirit is the same: reverence for Parshvanath, self-discipline, and spiritual vows. The exact tithi and some regional customs may differ between Digambara and Śvetāmbara communities.

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