One has to learn tolerance in the face of dualities (Chapter 2 Text 45)
- Hare Krishna Friends,Chapter 2: Contents of the Gita Summarized
When the activities for sense gratification, namely the karma-kanda chapter, are finished, then the chance for spiritual realization is offered in the form of the Upanisads, which are part of different Vedas, as the Bhagavad-gita is a part of the fifth Veda, namely the Mahabharata. The Upanisads mark the beginning of transcendental life.
As long as the material body exists, there are actions and reactions in the material modes. One has to learn tolerance in the face of dualities such as happiness and distress, or cold and warmth, and by tolerating such dualities become free from anxieties regarding gain and loss. This transcendental position is achieved in full Krsna consciousness when one is fully dependent on the good will of Krsna.
.......continued.Source As It Is by HDG. A.C. BhaktiVedanta Swami Srila Prabhupada.