Transliteration
tam uvaca hrsikesah prahasann iva bharata
senayor ubhayor madhye visidantam, idam vacah
sri-bhagavan uvaca
asocyan anvasocas tvam prajna-vadams ca bhasase
gatasun agatasums ca nanusocanti panditah
Translation
O descendant of Bharata, at that time Krsna, smiling, in the midst of both the armies, spoke the following words to the grief-stricken Arjuna. The Blessed Lord said: While speaking learned words, you are mourning for what is not worthy of grief. Those who are wise lament neither for the living nor the dead.
Purport
The above Shloka is the start of Buddhi-Sankya Yoga. In this very first line, Bhagvan Shri Krishna tells that the reason why Arjuna is grieving is not valid reason at very first place and doing so is nothing but ignorance. In second line of same shloka, Bhagvan Shri Krishna gives the real state of a person who is knowledgeable. A true knowledgeable person does not grieve either for those who have gone neither for those coming.
Now this might be very difficult for a normal person to understand. After all somebody going from this planet is a matter of grief. But then the knowledge of Shrimad Bhagvad Gita starts from where the mortal knowledge ends.
From next Shloka onwards till Shloka#30 Bhagvan Shri Krishna revealed Arjuna about the secret of life, soul and life. Later from Shloka #31 onwards Bhagvan Shri Krishna explains the secret of duties and other subjects, which we would be talking in coming days.
This whole chapter in summary is called as Buddhi-sankhya Yoga.
