Bhagavad Gita 18.11
But since those still in the body cannot entirely avoid action, in their case, the abandonment of the fruit of action is considered as complete renunciation.
न हि देहभृता शक्यं त्यक्तुं कर्माण्यशेषतः।यस्तु कर्मफलत्यागी स त्यागीत्यभिधीयते॥na hi dehabhṛtā śakyaṃ tyaktuṃ karmāṇyaśeṣataḥ|yastu karmaphalatyāgī sa tyāgītyabhidhīyate||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).