Adhyāya 166: Kṛtaghna-doṣa (कृतघ्नदोषः) — the fault of ingratitude and the limits of expiation
भ्रूगहा55हवमध्ये तु शुद्ध्यते शस्त्रपातत:
bhrūgāhāhavamadhye tu śuddhyate śastrapātataḥ
Bhīṣma said: Even in the very midst of a fierce battle, one becomes purified through the falling (use) of weapons—i.e., by meeting the ordeal of combat in accordance with one’s duty, without deceit or unrighteous intent.
भीष्म उवाच
Bhīṣma frames righteous combat (performed as kṣātra-dharma, without adharma such as treachery) as a means of moral purification: enduring and engaging the hardships of battle in a duty-bound way can cleanse one of faults, much like other prescribed disciplines.
In Śānti Parva’s instruction on dharma after the war, Bhīṣma continues advising on the duties and ethical framework of warriors. This line emphasizes that even the violent arena of battle can be spiritually consequential when governed by dharma.