Arjuna said :
योऽयं योगस्त्वया प्रोक्तः साम्येन मधुसूदन ।
एतस्याहं न पश्यामि चंचलत्वात् स्थितिं स्थिराम् ॥ ३३ ॥
yo’yaṃ yogastvayā proktaḥ sāmyena madhusūdana .
etasyāhaṃ na paśyāmi caṃcalatvāt sthitiṃ sthirām .. 33 ..
This Yoga in equanimity, taught by Thee, O Destroyer of Madhu,—I see not its steady continuance, because of the restlessness (of the mind.)
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This is a well-known fact :