It seems you might be referring to Paryushana (sometimes spelled as Paryushan), which is one of the most important annual festivals in Jainism.

Paryushana Celebration in Jainism

Paryushana is a time of spiritual upliftment and deep reflection for Jains. The word "Paryushana" means "to stay in one place," signifying a time of introspection, fasting, and increasing spiritual intensity.

When is it Celebrated?

• Shwetambar Jains: Paryushana lasts for 8 days, usually in August or September.
• Digambar Jains: The festival is observed for 10 days and is called Das Lakshan Parva.

Key Features of Paryushana:

1. Fasting: Many Jains undertake various forms of fasting—from complete fasting (no food or water) to partial fasting (restrictions on types or quantity of food).
2. Prayers and Rituals: Special prayers, recitation of scriptures (like the Kalpasutra), and participation in religious discourses are central.
3. Confession and Forgiveness: The last day is known as Samvatsari (for Shwetambar) or Kshamavani (for Digambar), which is dedicated to seeking forgiveness from all living beings for any harm caused knowingly or unknowingly. The phrase "Micchami Dukkadam" is exchanged, meaning "May my misdeeds be forgiven."
4. Charity and Compassion: Jains are encouraged to practice ahimsa (non-violence) more strictly, avoid harm to even the smallest of creatures, and engage in acts of charity.
5. Self-Discipline: Apart from fasting, Jains also practice self-restraint in other areas—avoiding certain foods, limiting possessions, and focusing on spiritual development.

Significance

The purpose of Paryushana is to purify the soul by shedding accumulated karma and to cultivate virtues like forgiveness, humility, and self-restraint.

Summary

Paryushana is a sacred period of self-purification, penance, and spiritual renewal, marked by fasting, prayer, reflection, and a focus on forgiveness and non-violence in Jainism.