Chapter 2, Verse 48
"Do your work
In the peace of Yoga.
Free from selfish desires,
Be not moved
In success nor failure.
Yoga is equanimity,
A peace that is ever the same."
Father Bede Griffiths:
Samatva is evenness of mind or equanimity. Leaving the fruit of our work to God means that if we succeed, then we are happy but not exalted, while if we fail, we are sorry but not depressed. When ego is master, we become over-excited by success and depressed by failure, and it is this reaction which binds. I suppose almost everybody works with some degree of egoism, but we can always test the degree of our egoism by the extent of our reactions.
There is a danger that if we embrace this notion of indifference to results, it may seem as if work is of no importance and some may be encouraged to work half-heartedly, but this is a misunderstanding. The point is to put your whole heart into the work, do all you can, and surrender the whole thing to God."
"It is because of ignorance that we have hope and fear, wrath and transient joy. However, it is possible to perform works with a perfect serenity and freedom. Therefore it is Buddhi Yoga that is first enjoined on Arjuna. To act aware of the Self in all out of its equal serenity and to not run about in a thousand directions under the thousand impulses of our superficial self is the essence of Buddhi Yoga, the Yoga of discernment."