Bhagavad Gita 3.30 Chapter 3, Verse 30

मयि सर्वाणि कर्माणि संन्यस्याध्यात्मचेतसा ।
निराशीर्निर्ममो भूत्वा युध्यस्व विगतज्वरः ॥३.३०॥

mayi sarvāṇi karmāṇi saṃnyasyādhyātmacetasā
nirāśīrnirmamo bhūtvā yudhyasva vigatajvaraḥ

Meaning

Dedicating all actions to me, with your mind fixed on the Self, free from hope and the sense of "mine", and without inner fever, fight.

Newly written by Bhajan Dhun — scholarly review in progress.

Reference: Bhagavad Gita 3.30 (Chapter 3, The Yoga of Action (Karma Yoga), Verse 30)