Bhagavad Gita 4.20
Having surrendered all claim to the results of his actions, he is always contented and independent; in reality, he does nothing, even though he appears to be acting.
त्यक्त्वा कर्मफलासङ्गं नित्यतृप्तो निराश्रयः।
कर्मण्यभिप्रवृत्तोऽपि नैव किञ्चित्करोति सः॥tyaktvā karmaphalāsaṅgaṃ nityatṛpto nirāśrayaḥ|
karmaṇyabhipravṛtto'pi naiva kiñcitkaroti saḥ||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).