Bhagavad Gita Chapter 6, Verse 32

आत्मौपम्येन सर्वत्र समं पश्यति योऽर्जुन | सुखं वा यदि वा दुःखं स योगी परमो मतः ||

ātmaupamyena sarvatra samaṁ paśyati yo 'rjuna sukhaṁ vā yadi vā duḥkhaṁ sa yogī paramo mataḥ

He who, through the likeness of the Self, O Arjuna, sees reality everywhere, be it pleasure or pain, is regarded as the highest Yogi.

Krishna describes the highest yogi who sees equality everywhere. 'Ātmaupamyena sarvatra samaṁ paśyati yo 'rjuna'—O Arjuna (arjuna), one who (yaḥ), through the likeness (aupamyena) of the Self (ātma), sees (paśyati) equally (samam) everywhere (sarvatra). This means: the yogi who sees everything through comparison with the Self—seeing the same Self in all, recognizing the likeness, the sameness. This yogi sees equality everywhere—not distinctions, not differences, just equality. 'Sukhaṁ vā yadi vā duḥkhaṁ'—whether (yadi) it is pleasure (sukham) or (vā vā) pain (duḥkham). This means: the yogi sees equality even in pleasure and pain—not favoring pleasure, not avoiding pain, but seeing them equally. 'Sa yogī paramo mataḥ'—that (saḥ) yogi (yogī) is considered (mataḥ) the highest (paramaḥ). This means: this yogi—who sees equality everywhere through the likeness of the Self, who sees pleasure and pain equally—is the highest yogi, the supreme yogi. This is the culmination: seeing equality everywhere, through Self-likeness, even in pleasure and pain—this is the highest state.