The Gita itself is set in a battlefield, not in the Himalayas, or in a forest. Arjuna is face-to-face with a problem born of conflict between his familial affections and the call of duty. On one side, it seems necessary for him to perform his duty, which is to fight the war. Then, there is another equally powerful pull — his affection for his family and teachers, which conflicts with the concept of duty. Caught between the horns of duty and affection, Arjuna is confused as he stands between the two forces on the battlefield.
The battle has been declared because Duryodhana has usurped the kingdom. The Pandavas had tried to avoid war by asking Krishna to act as a mediator. Duryodhana wouldn't give the kingdom back nor share it with the Pandavas. He would not give a district, a county, a village with five houses, nor a house with five rooms; not even a square inch of land would he give. He said, "Let them either go back into the forest or meet me in the battlefield." There was no way of avoiding war.
When Arjuna looked across the battlefield, he found highly respected people — Drona, his own teacher, Bhishma, his grandfather, and many relatives — with whom he had to fight. He said, "What is the use of fighting all these people? Without killing them, I'm not going to get the kingdom back. And what is the use of getting the kingdom back by destroying the people in whose company I would be happy?" Arjuna saw that in war nobody is a winner. "I see a black, dark future; therefore, I'm not interested in this fight." Arjuna gave up his bow and arrows.
While caught between the call of duty and his emotions, Arjuna begins to appreciate a fundamental problem — the problem of a human being. That problem takes possession of his mind and he wants to find a solution. Finding a teacher in Lord Krishna, he presents himself to Krishna as a shishya, a disciple. Arjuna was always a devotee, but not a shishya; he finds himself a shishya on the battlefield. Lord Krishna accepts Arjuna as a disciple and teaches him in the succeeding chapters of the Gita.