Shloka 16
Adhyāya 166: Kṛtaghna-doṣa (कृतघ्नदोषः) — the fault of ingratitude and the limits of expiation
विज्वैदेवैश्व साध्यैश्न ब्राह्मणैश्व महर्षिभि: । आपत्सु मरणाद् भीतैर्विधि: प्रतिनिधीकृत:
viśvaidevaiś ca sādhyaiś ca brāhmaṇaiś ca maharṣibhiḥ | āpatsu maraṇād bhītair vidhiḥ pratinidhīkṛtaḥ ||
毗湿摩说：“即便是毗湿维天众（Viśvedevas）与萨提耶众（Sādhyas），连同婆罗门与大圣仙，在灾厄之时为死惧所迫，也确立了代行之理——为每一条所制之法设立相应的替代之则——使得当严守不复可能时，正法仍得以保存。”
भीष्म उवाच
Educational Q&A
In emergencies (āpatsu), dharma allows regulated substitution (pratinidhi) for strict rules (vidhi), so that the spirit and continuity of dharma are maintained when literal performance is not feasible.
Bhishma is explaining principles of āpaddharma in the Śānti Parva, citing even divine and sage authorities (Viśvedevas, Sādhyas, Brahmins, Maharṣis) as having sanctioned representative substitutes for prescribed acts under life-threatening distress.