इन्द्रियाणां हि चरतां यन्मनोऽनु विधीयते । तदस्य हरति प्रज्ञां वायुर्नावमिवाम्भसि ॥६७॥
indriyāṇāḿ hi caratāḿ yan mano 'nuvidhīyate tad asya harati prajñāḿ vāyur nāvam ivāmbhasi
indriyāṇām — of the senses; hi — certainly; caratām — while roaming; yat — with which; manaḥ — the mind; anuvidhīyate — becomes constantly engaged; tat — that; asya — his; harati — takes away; prajñām — intelligence; vāyuḥ — wind; nāvam — a boat; iva — like; ambhasi — on the water.
Just as a strong wind sweeps a boat off its chartered course on the water, even one of the senses on which the mind focuses can lead the intellect astray.
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 Mahārāja Ambarīṣa, all of the senses must be engaged in Kṛṣṇa consciousness, for that is the correct technique for controlling the mind.