“Padikkamāmi nindāmi garihāmi appāṇaṁ vosirāmi” is said whenever you confess a fault and decide to give it up.

In practice, you say it:

1. During Pratikraman

- In the Karemi Bhante Sāmāiyaṁ sutra (Samayik vow). - In places like Guru Vandana, Samvatsari pratikraman, etc. There it means: - Padikkamāmi – I do pratikraman / repent. - Nindāmi – I censure/blame this fault. - Garihāmi – I strongly condemn it. - Appāṇaṁ vosirāmi – I separate my soul from this fault / I renounce it.

1. After Ālochana (confessing a specific sin)

- When you remember some wrong you did (by mind, speech, or body), you mentally admit it and then say this line to show: - I repent, I condemn it, and I resolve not to repeat it.

1. When taking small vows (pachchakkhān / upvās, etc.)

- Often, at the end of a vow statement (e.g., for upvās, samayik, etc.) you may see or say “…appāṇaṁ vosirāmi” to show you are renouncing wrong actions for that period.

Traditions:

• The exact words “padikkamāmi nindāmi garihāmi appāṇaṁ vosirāmi” are mainly in Śvetāmbara pratikraman sutras.
• Digambar texts use similar meanings (repent–condemn–renounce the fault), though wording may differ; the bhāva (inner meaning) is the same:

- accept the fault, - sincerely repent, - firmly decide to leave it.

So, you say this line whenever you are truly repenting a fault and wanting to cut your connection with it, especially in daily, pakkhi, devāsī, chauvihārī and Samvatsarī pratikraman.

You can see related explanations on JainKnowledge here:

• Meaning and context of “garihāmi vosirāmi”
• Example usage in pachchakkhān (upvās)