Bhagavad Gita Chapter 18, Verse 6

एतान्यपि तु कर्माणि सङ्गं त्यक्त्वा फलानि च | कर्तव्यानीति मे पार्थ निश्चितं मतमुत्तमम् ||

etāny api tu karmāṇi saṅgaṁ tyaktvā phalāni ca kartavyānīti me pārtha niścitaṁ matam uttamam

O Partha, these actions should indeed be performed, having abandoned attachment and fruits. This is My conclusive and supreme opinion.

Krishna gives his conclusive teaching on how to perform prescribed duties. 'Etāny api tu karmāṇi'—these actions (yajña, dāna, tapaḥ) should indeed be performed. 'Saṅgaṁ tyaktvā phalāni ca'—having abandoned attachment (saṅga) and fruits (phalāni). This is the key teaching: you perform the actions (kartavyāni), but you abandon attachment to them and attachment to their results. You don't abandon the duty—you abandon attachment to the duty and attachment to outcomes. 'Niścitaṁ matam uttamam'—this is My conclusive and supreme opinion. This is the definitive answer to Arjuna's question: true renunciation means performing duty while relinquishing attachment to both the action and its fruits. This is the path—not abandoning action but acting without attachment. This synthesizes renunciation and action: you perform duty (not renouncing it) but with detachment (relinquishing attachment).