Puṣkara-Śapatha Itihāsa (Agastya–Indra Dispute at the Tīrthas) | पुष्कर-शपथ-आख्यानम्
भीष्म उवाच मासार्धमासोपवासाद् यत् तपो मन्यते जन: । आत्मतन्त्रोपघाती यो न तपस्वी न धर्मवित्
bhīṣma uvāca māsa-ardha-māsa-upavāsād yat tapo manyate janaḥ | ātma-tantro-paghātī yo na tapasvī na dharma-vit ||
भीष्म म्हणाले— राजन्! जे लोक पंधरा दिवस किंवा एक महिना उपवास करून त्यालाच तप मानतात, ते व्यर्थच आपल्या देहाला क्लेश देतात. असा स्वेच्छाचारी व आत्मघातकी मनुष्य न तपस्वी असतो, न धर्मज्ञ.
भीष्म उवाच
Bhishma teaches that austerity is not simply prolonged fasting; without right understanding and disciplined purpose, such fasting becomes self-harm and does not make one a true ascetic or a knower of dharma.
In the Anushasana Parva, Bhishma instructs King Yudhishthira on dharma. Here he critiques the popular notion that a fortnight- or month-long fast by itself constitutes tapas, emphasizing ethical discernment over mere bodily mortification.