यं हि न व्यथयन्त्येते पुरुषं पुरुषर्षभ।समदुःखसुखं धीरं सोऽमृतत्वाय कल्पते॥
yaṃ hi na vyathayantyete puruṣaṃ puruṣarṣabhasama-duḥkha-sukhaṃ dhīraṃ so ’mṛtatvāya kalpate
Word by word
The verse says
The one these cannot shake — steady, the same in pain and in pleasure — that person is fit for what does not die.
In plain words
The reward for verse 14, stated immediately.
Someone who is not thrown by the coming and going is dhīra — steady. And the mark of that steadiness is being the same in pain and in pleasure.
Not indifferent to both. The same person in both.
Where you've felt this · in friendship
A friend who is recognisably themselves whether things are going well or badly. They are not flat. They laugh and they grieve. But you never have to work out which version of them you are getting before you speak.
Going deeper
Sama-duḥkha-sukham — equal in sorrow and joy. This compound will return again and again; it is one of the Gita's core descriptions of a finished person.
It is often heard as coldness, and that reading does not survive contact with the rest of the book. The same person is described in Chapter 12 as warm, friendly, compassionate to all beings. Whatever sama means, it is compatible with a great deal of feeling.
What it rules out is being governed. The difference is between weather and climate. A steady person still has weather. What they do not have is a self that reorganises itself every time the weather changes.
Then the strange promise at the end: such a person becomes fit for amṛtatvam, deathlessness. Not earns it. Becomes eligible.
That is a precise choice of word. What is being described is not a reward for good behaviour. It is a capacity. A mind that stops being dragged by every contact becomes able to notice something that was always there — which is the claim verses 16 to 25 are about to unpack.