तेन द्वारेण शत्रुभ्य: क्षीयते सबलो रिपु:,प्रमादरूप छिद्रके कारण बलवान शत्रु भी अपने शत्रुओंद्वारा मारा जाता है
tena dvāreṇa śatrubhyaḥ kṣīyate sa-balo ripuḥ | pramāda-rūpa-chidrake kāraṇāt balavān śatruḥ api sva-śatrubhiḥ māryate ||
Through that very ‘doorway’ (a breach), even an enemy who possesses strength and support is worn down by his foes. For negligence itself becomes a gap; because of such a flaw, even a powerful adversary is brought to ruin—slain by his own enemies.
अर्जुन उवाच
Negligence (pramāda) creates a ‘breach’ (chidra) through which even a strong, well-supported opponent can be weakened and destroyed; vigilance is an ethical and strategic necessity.
Arjuna states a general principle of conflict and governance: enemies exploit openings caused by carelessness, so a powerful rival can still be overcome if he becomes negligent.