Answer

No, it is generally not compulsory to do Chovihar today if you want to do Tapasya tomorrow.

However, doing Chovihar the previous night is considered very good and spiritually beneficial, because it helps prepare the body and mind for Tapasya with more discipline and purity.

Explanation

In Jain practice:

• Chovihar means not taking food or water after sunset.
• Tapasya may include different forms such as Ekasana, Beasana, Upvas, Ayambil, etc.

For most Tapasya, the main rule is to follow the specific discipline of that Tapasya on the actual day.

For example:

• If you are doing Upvas tomorrow, you should follow the rules of Upvas tomorrow.
• If you are doing Ayambil, you should follow Ayambil rules on that day.
• If you are doing Ekasana or Beasana, you follow those rules during that day.

Doing Chovihar the night before is recommended by many as a good practice, but it is not universally compulsory for every Tapasya.

Spiritual Understanding

Chovihar supports Tapasya because it:

• Reduces attachment to taste and food
• Encourages self-control
• Helps avoid unnecessary harm to subtle living beings at night
• Makes the mind calmer for spiritual practice

Takeaway

If you can do Chovihar today, it is spiritually excellent. But if you cannot, you may still do Tapasya tomorrow with sincerity, proper intention, and discipline.