Sanskrit
तस्मात्त्वमिन्द्रियाण्यादौ नियम्य भरतर्षभ । पाप्मानं प्रजहि ह्येनं ज्ञानविज्ञाननाशनम् ॥
tasmāt tvam indriyāṇy ādau niyamya bharatarṣabha pāpmānaṃ prajahi hy enaṃ jñānavijñānanāśanam
Translation
Therefore, O best of the Bhâratas, mastering first the senses, do thou slay this thing of sin, destructive of wisdom and knowledge.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
A concrete instruction that follows from verse 40’s map: start with the senses, since they’re the outermost and most accessible layer of desire’s territory. “Slay” keeps the martial framing from verse 37’s “foe” going, aiming the whole discourse’s language of battle inward as much as outward — which matters given that Arjuna’s actual crisis is about an external battle.