Bhagavad Gita 18.41

ब्राह्मणक्षत्रियविशां शूद्राणां च परंतप।कर्माणि प्रविभक्तानि स्वभावप्रभवैर्गुणैः॥

brāhmaṇakṣatriyaviśāṃ śūdrāṇāṃ ca paraṃtapa |karmāṇi pravibhaktāni svabhāvaprabhavairguṇaiḥ ||

Of Brahmanas, Kshatriyas, Vaisyas, and Sudras, O Arjuna, the duties are distributed according to the qualities born of their own nature.

O Arjuna! The duties of spiritual teachers, the soldiers, the traders, and the servants have all been fixed according to the dominant quality in their nature.

Our plain-language meaning of this verse is waiting for scholar review.