Siddhi Tap is a severe form of tapas (austerity) aimed at attaining spiritual progress or liberation (moksha) and the perfection of the soul (siddhi). In Jain practice, siddhi means a state of spiritual attainment, often associated with ultimate purification and removal of karma.

Key points:

• It is a strict austerity, often involving extended fasting and intense self-control.
• The purpose is to destroy karma, purify the soul, and move toward liberation; not for seeking worldly powers.
• It is not listed as a single canonical vow with a fixed recipe in all traditions, but it aligns with the Jain emphasis on bhāya/tapas (external and internal austerities) and the path to siddhi.

Notes:

• Different Jain communities may describe or practice such austerities in varied ways (regional or sect-specific customs). The core idea remains purifying the soul and advancing toward moksha.
• In Jain scriptures, the broader category of tapas (external and internal) is the established framework; Siddhi Tap is understood as an especially rigorous form within that framework.

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