Bhagavad Gita · 18.57

चेतसा सर्वकर्माणि मयि संन्यस्य मत्परः।बुद्धियोगमुपाश्रित्य मच्चित्तः सततं भव॥

chetasā sarva-karmāṇi mayi sannyasya mat-paraḥ buddhi-yogam upāśhritya mach-chittaḥ satataṁ bhava

Mentally renouncing all actions in Me, regarding Me as the Supreme, resorting to the yoga of discrimination, fix your mind constantly on Me.

— Bhagavad Gita 18.57

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)