Adhyāya 166: Kṛtaghna-doṣa (कृतघ्नदोषः) — the fault of ingratitude and the limits of expiation
द्वे तस्य त्रीणि वर्षाणि चत्वारि सहसेविनि । कुचर: पज्चवर्षाणि चरेद् भैक्ष्यं मुनिव्रत:
dve tasya trīṇi varṣāṇi catvāri sahasevini | kucaraḥ pañcavarṣāṇi cared bhaikṣyaṃ munivrataḥ ||
Bhīṣma said: If a person has kept company with that fallen man for two, three, or four years, then—having adopted a sage-like vow—he should live by begging and wander upon the earth for the same number of years. But one who has associated with him for five years should likewise practice the mendicant life for five years.
भीष्म उवाच
Association with serious wrongdoing is treated as ethically consequential; purification requires proportionate, time-bound austerity—living as a mendicant under a sage-like vow for as many years as the association lasted.
Bhīṣma, instructing the king in Śānti Parva on law and expiation, specifies a graded penance: those who remained in the company of a fallen man for 2–5 years must wander and subsist on alms for the corresponding duration, as part of restoring dharmic order.