BG 6.34
चञ्चलं हि मन: कृष्ण प्रमाथि बलवद्दृढम् ।
तस्याहं निग्रहं मन्ये वायोरिव सुदुष्करम् ॥ ३४ ॥
cañcalaṁ hi manaḥ kṛṣṇa
pramāthi balavad dṛḍham
tasyāhaṁ nigrahaṁ manye
vāyor iva su-duṣkaram
cañcalam — flickering; hi — certainly; manaḥ — mind; kṛṣṇa — O Kṛṣṇa; pramāthi — agitating; balavat — strong; dṛḍham — obstinate; tasya — its; aham — I; nigraham — subduing; manye — think; vāyoḥ — of the wind; iva — like; suduṣkaram — difficult.
For the mind is restless, turbulent, obstinate and very strong, O Kṛṣṇa , and to subdue it is, it seems to me, more difficult than controlling the wind.
The mind is so strong and obstinate that it sometimes overcomes the intelligence, although mind is supposed to be subservient to the intelligence. For a man in the practical world who has to fight so many opposing elements, it is certainly very difficult to control the mind. Artificially, one may establish a mental equilibrium toward both friend and enemy, but ultimately no worldly man can do so, for this is more difficult than controlling the raging wind. In the Vedic literatures it is said: