सुस्थेयं क्षुधधारासु निशितासु महीपते । धारणासु तु योगस्य दुःस्थेयमकृतात्मभि:,पृथ्वीपते! छुरेकी तीखी धारपर कोई सुखपूर्वक खड़ा रह सकता है; किंतु जिनका चित्त शुद्ध नहीं है, ऐसे मनुष्योंका योगकी धारणाओंमें स्थिर रहना नितान्त कठिन है
su-stheyaṁ kṣudhā-dhārāsu niśitāsu mahīpate | dhāraṇāsu tu yogasya duḥstheyam akṛtātmabhiḥ pṛthvīpate ||
Bhīṣma said: “O king, one may stand with ease even upon the sharp edge of a blade; but for those whose inner self is unrefined and undisciplined, to remain steady in the practices of yogic concentration (dhāraṇā) is exceedingly difficult.”
भीष्म उवाच
External hardships can be borne, but true steadiness in yogic concentration demands an inwardly purified, disciplined mind; without self-mastery (kṛtātman), dhāraṇā becomes extremely difficult.
In the Śānti Parva’s instruction to the king, Bhīṣma emphasizes the rigor of inner spiritual practice, using the razor-edge image to contrast physical endurance with the greater challenge of mental and ethical self-discipline required for yoga.