Chapter 3 · verse 35 · gita.yoga.org

Bhagavad Gita 3.35

श्रेयान्स्वधर्मो विगुणः परधर्मात्स्वनुष्ठितात्। स्वधर्मे निधनं श्रेयः परधर्मो भयावहः

Better is one's own duty, though devoid of merit, than the duty of another well discharged. Better is death in one's own duty; the duty of another is fraught with fear.