In Jainism, the practice of Siddhi Tap (also spelled Siddhi Tap or Siddhi-tapa) is a special type of austerity (tapasya) observed by some ascetics and devout householders, especially during auspicious periods like the Chaturmas or holy festivals. Siddhi Tap is not attributed to a single individual as its initiator; rather, it is a tradition that has developed within Jain spiritual practice over centuries.

The Siddhi Tap is considered a rigorous form of fasting and self-discipline, often involving multiple days of alternate fasting (upavasa) and partial fasting (ayambil or ekasana). Its purpose is to purify the soul, accumulate spiritual merit (punya), and progress on the path to liberation (moksha).

While ancient Jain scriptures describe various types of tapas (austerities), including Siddhi Tap, there is no mention of a specific person who first initiated this practice. Instead, it is regarded as an evolved form of tapasya that follows the broader teachings and examples set by the Tirthankaras (spiritual victors) and prominent Jain monks.

If you are interested in the details or procedure of Siddhi Tap, or its significance in Jainism, please let me know!