One who, O Arjuna, sees the same everywhere by likening others to himself, whether in pleasure or in pain — that yogi is considered the highest.
Explanation
Krishna continues describing the person of yoga (spiritual discipline), saying the highest yogi measures others by himself (ātmaupamya). Just as he wants pleasure and dislikes pain, he sees that every being feels the same, and so he treats their joys and sorrows as his own. Commentators differ on emphasis: some read this as a vision of the one Self in all beings, others as compassionate, ethical empathy toward all.