Posh Dashmi (Poṣa‑daśamī) is an important Jain festival that centers on the birth and life of Parshvanath, the 23rd Tirthankar.

Key points about its importance:

• It honors Parshvanath and is often celebrated as Parshvanath‑jayantī.
• It is observed for three days—the 9th, 10th, and 11th days of the dark half (vadī) of the Poṣha/Māgsar period. The exact dates vary each year with the lunar calendar, and regional Panchangs may shift by a day. Digambar and Śvetāmbar calendars are close but can have small differences. The essence remains the same: devotion to Parshvanath, self‑discipline, and spiritual progress. ( jainknowledge.com)
• Common practices during these days include temple worship of Parshvanath, listening to his life stories, singing his praises, and performing rituals such as a lamp ceremony. Devotees may undertake vows, fast partially or fully, and engage in prayers and contemplation to purify mind and conduct. ( jainknowledge.com)
• The festival is observed by both Digambara and Śvetāmbara Jains; calendar calculations may differ by region, but the purpose—to gain peace, purity of mind, and progress toward moksha—remains the same. ( jainknowledge.com)

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