B.G 6.24 and 25
संङ्कल्पप्रभवान्कामांस्त्यक्त्वा सर्वानशेषतः। मनसैवेंद्रियग्रामं विनियम्य समन्ततः ॥२४॥
saṁṅkalpaprabhavānkāmāṁstyaktvā sarvānaśeṣataḥ। manasaiveṁdriyagrāmaṁ viniyamya samantataḥ ॥24॥
शनैः शनैरुपरमेद्बुद्ध्या धृतिगृहीतया। आत्मसंस्थं मनः कृत्वा न किञ्चिदपि चिन्तयेत् ॥२५॥
śanaiḥ śanairuparamedbuddhyā dhr̥tigr̥hītayā। ātmasaṁsthaṁ manaḥ kr̥tvā na kiñcidapi cintayet ॥25॥
Having abandoned all desires arising from intentions without a residue; controlling the group of senses with the mind, indeed from all sides; gradually, slowly, one should withdraw with the help of firm intelligence. Having made the mind established in the Lord, one should certainly not think of anything else.
Gīta Bhāshya 6.24 and 25
'sarvān' - all topics; 'aśeṣataḥ' - Even on a single topic, a small amount of desire should not be left at any point in time. The word 'eva' provides exclusivity to control of mind as a means. The control of the mind and delighting in the lord within are the causes for such an intelligence.
The word 'sarvān' refers to 'all topics'. The word 'aśeṣataḥ' means 'Even on a single topic, a small amount of desire should not be left at any point in time'. Indeed, it is possible to control only by the mind, not by others. Hence, the word 'eva', i.e. 'only', is used.
The cause of such intelligence is because of control of the mind and also delighting in the Lord within.
