Bhagavad-gītā 18.41
BG 18.41
Open the full passageब्राह्मणक्षत्रियविशां शूद्राणां च परन्तप । कर्माणि प्रविभक्तानि स्वभावप्रभवैर्गुणैः ॥४१॥
Sanskrit
brāhmaṇa-kṣatriya-viśāṁ śūdrāṇāṁ ca parantapa karmāṇi pravibhaktāni svabhāva-prabhavair guṇaiḥ
Translation
Brāhmaṇas, kṣatriyas, vaiśyas and śūdras are distinguished by the qualities born of their own natures in accordance with the material modes, O chastiser of the enemy.