Bhagavad Gita · Chapter 3: The Path of Action
Bhagavad Gita 3.41
तस्मात्त्वमिन्द्रियाण्यादौ नियम्य भरतर्षभ ।
पाप्मानं प्रजहि ह्येनं ज्ञानविज्ञाननाशनम् ॥
tasmāttvamindriyāṇyādau niyamya bharatarṣabha | pāpmānaṃ prajahi hyenaṃ jñānavijñānanāśanam ||
Therefore, best of the Bharatas, first bring the senses under control, and then strike down this sinful thing, the destroyer of knowledge and realization.
Modern context
The practical advice follows from the last verse: begin with the senses, because they are the outermost gate and the easiest one to manage. It is much simpler not to keep sweets in the house than to resist them at midnight. The verse names two things that desire destroys: jnana, what we have learned, and vijnana, what we have realized for ourselves. A craving can make a person act against both their education and their own experience.