Siddhitap (also Siddhi Tap) is one of the most rigorous forms of tapas (austerity) in Jainism. It is performed to purify the soul, reduce karmas, and progress toward liberation. In many traditions it is described as a specific fasting regimen, often involving long periods of alternating fasting days and days with a minimal meal, sometimes extended over several weeks.

Common understanding:

• Method: a highly austere fast that may involve alternating days of complete fasts (upvas) and days with a single meal (ekasana), often extended for a set number of days (a common pattern cited is around 36 days, though practices can vary by region and sect).
• Goal: deep purification of the soul, reduction of passions (kashayas), and progress toward moksha.
• Context: associated with intense penance in the lives of great Jain ascetics and in commemorations of Mahavira’s tapas.

Important note on tradition: the precise rules and number of days can differ between Digambar and Śvetambar communities, and local lineages may have their own variants. The essential idea remains: Siddhitap is an exceptionally demanding form of austerity aimed at spiritual purification.

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