Sankhaya Yog-Bhagavad Gita Chapter 2 [Contents of the Gita Summarized]
Krishna Said > Shaloka: 57
He who is without attachment, who does not rejoice when he obtains good, nor lament when he obtains evil, is firmly fixed in perfect knowledge.
There is always some upheaval in the material world which may be good or evil. One who is not agitated by such material upheavals, who is unaffected by good and evil, is to be understood to be fixed in Krsna consciousness. As long as one is in the material world there is always the possibility of good and evil because this world is full of duality. But one who is fixed in Krsna consciousness is not affected by good and evil, because he is simply concerned with Krsna, who is all-good absolute. Such consciousness in Krsna situates one in a perfect transcendental position called, technically, samadhi.