sthita-dhīr munir ucyate
duḥkheṣu — in the threefold miseries; anudvigna-manāḥ — without being agitated in mind; sukheṣu — in happiness; vigata-spṛhaḥ — without being interested; vīta — free from; rāga — attachment; bhaya — fear; krodhaḥ — and anger; sthita-dhīḥ — whose mind is steady; muniḥ — a sage; ucyate — is called.
One who is not disturbed in mind even amidst the threefold miseries or elated when there is happiness, and who is free from attachment, fear and anger, is called a sage of steady mind.
. . .
दुःखेष्वनुद्विग्नमनाः सुखेषु विगतस्पृहः ।
वीतरागभयक्रोधः स्थिधीर्मुनिरुच्यते ॥ ५६ ॥