Bhagavad Gita 2.56
दु:खेष्वानुद्विग्नमना: सुखेषु विगतस्पृह: |
वीतरागभयक्रोधः स्थितधीर्मुनिरुच्यते
Translation
One whose mind remains undisturbed amidst misery, who does not crave for pleasure, and who is free from attachment, fear, and anger, is called a sage of steady wisdom.