Shloka 406
न्यायेन युध्यमानौ हि तद् वै सत्यं ब्रवीमि ते । मैंने यह समाचार भी सुना था कि भीष्म और द्रोणाचार्य मार गिराये गये, परंतु मैं तुमसे यह सच्ची बात कहता हूँ कि ये भीष्म और द्रोण यदि समरभूमिमें न्यायपूर्वक युद्ध करते होते तो इन्हें साक्षात् वज्रधारी इन्द्र भी नहीं मार सकते थे
nyāyena yudhyamānau hi tad vai satyaṃ bravīmi te |
For if those two were fighting in accordance with justice and the proper rules of battle, then—this I tell you as the plain truth—no one could overcome them. Even Indra himself, the wielder of the thunderbolt, would not be able to slay Bhīṣma and Droṇa were they engaged in righteous combat.
वैशम्पायन उवाच
Educational Q&A
The verse underscores that adherence to nyāya (just, rule-bound conduct) in war confers moral and even practical invincibility; Bhīṣma and Droṇa could be brought down only when the fight departed from strict dharma-yuddha norms.
Vaiśampāyana emphasizes to his listener that although news has been heard of Bhīṣma and Droṇa being slain, in truth they were so formidable that if they had been fighting strictly according to the rules of righteous battle, not even Indra could have killed them.