indriyanam hi caratam
yan mano 'nuvidhiyate
tad asya harati prajnam
vayur navam ivambhasi
indriyanam—of the senses; hi—certainly; caratam—while herding over; yat—that; manah—mind; anuvidhiyate—becomes constantly engaged; tat—that; asya—his; harati—takes away; prajnam—intelligence; vayuh—wind; navam—a boat; iva—like; ambhasi—on the water.
As a boat on the water is swept away by a strong wind, even one of the senses on which the mind focuses can carry away a man's intelligence.
Unless all of the senses are engaged in the service of the Lord, even one of them engaged in sense gratification can deviate the devotee from the path of transcendental advancement. As mentioned in the life of Maharaja Ambarisa, all of the senses must be engaged in Krsna consciousness, for that is the correct technique for controlling the mind.
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