Chapter VI Sloka 22

y< lBXva capr< la-< mNyte naixk< tt>,
yiSmiNSwtae n Ê>oen gué[aip ivcaLyte

yaÕ labdhv˜ c˜paraÕ l˜bhaÕ 
manyate n˜dhikaÕ tata× |
yasminsthito na du×khena 
guruõ˜pi vic˜lyate ( 6|22)||

Which, having obtained, he thinks there is no other gain superior to it;
wherein established, he is not moved even by heavy sorrow,

Which: the gain or the realisation of the Self or the immortal Soul.
Wherein: in the all-blissful Self which is free from delusion and sorrow.
The Self is all-full and self-contained. All the desires are fulfilled when one attains Self-realisation. That is the reason why the Lord says. "There is no other acquisition superior to Self-realisation." If one gets himself established in the Supreme self within, he cannot be shaken even by heavy sorrow and pain, because he is mindless and he is identifying himself with the sorrowless and painless Brahman. One can experience pain and sorrow when he identifies himself with the body and the mind. If there is no mind there cannot be any pain. When one is under chloroform he feels no pain even when his hand is amputated, because the mind is withdrawn from the body.