Answer

For a 15-day tapasya, the best day to start is usually the day when your mind is stable, your body is ready, and your spiritual resolve is strong. In Jain Dharma, the right date is not only about a calendar day — it is about inner readiness and proper discipline.

Explanation

You can keep these points in mind:

• Choose a day when you are physically fit

Start only when your health can support the tapasya properly.

• Choose a day when your mind is calm and determined

Tapasya should begin with firm niyama and bhavna, not confusion or pressure.

• Prefer a spiritually supportive day

Many people like to begin on an auspicious Jain day, such as: - a holy tithi in the Jain calendar - during Chaturmas - during Paryushan or other spiritually significant periods - on a day recommended by your guru or upashray

• Avoid starting on a day of travel, stress, or interruption

A tapasya should begin in a peaceful setting with proper routine.

• Follow your local Jain tradition

Different Jain sanghs and acharyas may follow different panchang and vidhi. So it is wise to take guidance from your guru, sadhvi, sadhus, or temple leader.

Spiritual Understanding

In Jain Dharma, tapasya is not successful only because of an “auspicious date.” Its strength comes from:

• shuddha bhav — pure intention
• samyak sankalp — right resolve
• niyama — disciplined observance
• vinay — humility and obedience to guidance

So, the best start day is the one that helps you begin with faith, discipline, and inner purity.

Takeaway

There is no single fixed “perfect” day for everyone. For 15-day tapasya, choose a day that is spiritually suitable, physically manageable, and approved by your Jain guide. The most important thing is firm devotion and steady observance.