Mahabharata — Anushasana Parva, Shloka 25
अत्रेः तपोबलप्रकाशः तथा च्यवनस्य सोमाधिकारः
Atri’s Illumination by Tapas; Cyavana and Soma-Entitlement
इसके लिये प्रायश्रित्त और शान्तिहोम करना चाहिये। गायत्री-मन्त्र, रैवत साम, पवित्रेष्टि, कृष्माण्ड अनुवाक् और अघमर्षण मन्त्रका जप भी आवश्यक है ।।
tathocchiṣṭam athānyonyaṃ saṃprāśen nātra saṃśayaḥ | rocanā virajā rātrir majjanalālambhanāni ca ||
毗湿摩说：“切不可食他人之残余（ucchiṣṭa），也不可同席而食至于彼此分食残余——此规无疑。行毕所定赎罪之后，还应遵守净化与吉祥之行：如触碰已加持之物（如牛黄 gorocanā），守持‘无垢’之夜，并行沐浴等清洁仪轨及相关戒行。”
भीष्य उवाच
Educational Q&A
The verse stresses strict standards of purity in conduct: one should not consume another person’s leftovers or engage in mutual sharing of remnants, and after expiation one should complete purification with auspicious, ritually cleansing observances (notably bathing and related rites).
In the Anuśāsana Parva’s instruction on dharma and right conduct, Bhīṣma continues advising Yudhiṣṭhira on expiations and purity rules, specifying prohibited eating practices and the follow-up purificatory/auspicious acts to be undertaken after prāyaścitta.