Shloka 463
Adhyāya 166: Kṛtaghna-doṣa (कृतघ्नदोषः) — the fault of ingratitude and the limits of expiation
आत्मानं जुहुयादग्नौ समिद्धे तेन शुद्धयते । गर्भके बच्चेकी हत्या करनेवाला यदि युद्धमें शस्त्रोंके आधातसे मर जाय तो उसकी शुद्धि हो जाती है अथवा प्रज्वलित अग्निमें कूदकर अपने आपको होम दे तो वह शुद्ध हो जाता है
ātmānaṃ juhuyād agnau samiddhe tena śuddhyate |
Bhīṣma says that one may attain purification by offering oneself into a well-kindled fire; through that act one becomes cleansed. In the surrounding ethical discussion, this is presented as an expiatory means for grave wrongdoing—purification through self-sacrifice, whether by dying under weapons in battle or by self-immolation in a blazing fire.
भीष्म उवाच
Educational Q&A
Purification from severe sin is said to be attainable through extreme expiation: offering oneself into a well-kindled fire (or, in the broader passage, dying under weapons in battle). The emphasis is on self-surrender as a purificatory act within the dharma framework of prāyaścitta.
In Śānti Parva, Bhīṣma instructs Yudhiṣṭhira on dharma and expiations. Here he states a specific expiatory rule: one who offers oneself into a blazing fire becomes purified, presented amid discussion of remedies for grievous transgressions.