Answer

In Jain Dharma, Chhath and Attham are types of tapasya involving fasting.

• Chhath tap: Fasting continuously for 2 days.
• Attham tap: Fasting continuously for 3 days.

Usually, this means taking only boiled water during permitted times, according to one’s tradition, health, and guidance.

Explanation

In Jain practice:

• Upvas means one full day of fasting.
• Chhath is generally understood as two continuous upvas.
• Attham is generally understood as three continuous upvas.

These are forms of bahya tap, external austerity, practiced to reduce attachment to food, control desires, and strengthen self-discipline.

Spiritual Understanding

The purpose of Chhath and Attham is not only to avoid food, but to purify the soul by:

• Reducing attachment to the body
• Practicing self-control
• Increasing awareness of the soul
• Supporting repentance, prayer, svadhyay, and meditation

Fasting should be done with humility, right intention, and inner purity—not with pride or competition.

Takeaway

Chhath means a 2-day fast, and Attham means a 3-day fast, practiced as Jain tapasya for spiritual purification and self-control.