2-38

सुखदुःखे समे कृत्वा लाभालाभौ जयाजयौ ।
ततो युद्धाय युज्यस्व नैवम् पापमवाप्स्यसि ॥ ३८ ॥

sukhaduHkhe same kRtvA lAbhAlAbhau jayAjayau |
tato yuddhAya yujyasva naivam pApamavApsyasi || 38 ||

सुकदुःखे [sukaduHkhe] Happiness and sadness, लाभालाभौ [lAbhAlAbhau] profit and loss, जयाजयौ [jayAjayau] victory and defeat - समे कृत्वा [same kRtvA] count them all equally and ततः [tataH] in this way, युद्धाय युज्यस्व [yuddhAya yujyasva] engage in war. एवम् [evam] With this, पापम् न अवाप्स्यसि [pApam na avApsyasi] you will not beget misfortune.

Know the Self to be distinct from the body in the manner described, untouched by all the characteristics of the body. Know it to exist eternally. Knowing this, do not let your intellect be deformed by events caused by the usage of weapons. They are inevitable in battle, accompanied by joy and sorrow, loss and gain, victory and defeat.

Perform this war merely as your duty. Don’t be swayed by attachment to any possible outcome. By performing action this way, you will not beget misfortune - meaning you’re not trapped by sorrow in this world. You shall be free of material attachments and all limitations in the world that inhibit you.

After preaching the true nature of the Self in this way, Krishna starts to describe the pre-requisite to realize the true nature of the Self - Karmayoga, which is a way to attain moksha .