Upvas pachkan is the formal vow or declaration you recite before observing a fast (upvas) in Jainism. It sets the rules for the day—what you will eat or drink, and what practices you’ll follow (for example, whether you’ll eat solid food, drink water, or observe accompanying practices like Samayik or Pratikraman). The pachkan makes the fast intentional and binding.

• It is usually taken in the morning, before starting the fast, and can specify details such as:

- the type of upvas (e.g., sajala upvas with boiled water, or upvas without water), - the duration (often from sunrise to the next sunrise), - and any additional restraints (like avoiding certain foods or actions).

• Different Jain traditions (Shwetambar vs. Digambar) may have slight differences in the exact words or preferred formulations, but the core idea remains the same: a sincere, clear vow to observe the day’s fast and purification aims.

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