尼羯磨 1.161

1.161

不得覆藏他重罪乃至突吉羅惡說。若比丘尼知比丘尼犯波羅夷，不自舉、不白僧、不語人令知。後於異時，此比丘尼若休道、若滅擯、若遮不共僧事、若入外道；彼作如是言：「我先知此人犯如是如是罪。」彼非比丘尼，非釋種女，覆藏他重罪故。汝是中盡形壽不得犯，能持不？（答言：）能。

"You must not conceal another's grave offence, down to a duṣkṛta or ill-spoken word. If a bhikṣuṇī knows that a bhikṣuṇī has committed a pārājika, and does not bring it up herself, does not inform the saṃgha, and does not tell anyone to make it known, and later at another time, this bhikṣuṇī either abandons the path, or is cast out, or is prohibited from participating in saṃgha matters, or joins a non-Buddhist sect, and she says: 'I knew before that this person had committed such-and-such an offence,' she is not a bhikṣuṇī, not a daughter of the Śākyas, because she concealed another's grave offence. You must not violate this for the rest of your life; can you uphold it?" (She answers:) "I can."