Śrī Kṛṣṇa, the Supreme Personality of Godhead and the ideal spiritual master, spoke the philosophy of Bhagavad-gītā to Marshal Arjuna, His disciple. Here is a perfect example of the relationship between the spiritual master and the disciple. Arjuna was a most intimate friend of Śrī Kṛṣṇa, and thus Śrī Kṛṣṇa explained to him the essence of all scriptures, in the philosophy of Bhagavad-gītā.
Because we are always very busy in the discharge of our worldly duties, generally we do not wish to understand any philosophy except our mundane philosophy of the stomach and allied subjects. We have extended many branches and sub-branches of this philosophy of the belly in various directions, and thus we have hardly any time to understand the philosophy of gaining eternal life—for which we are perpetually struggling life after life.
Marshal Arjuna pretended to display philosophical ignorance and weakness, like an ordinary man, when with his chariot between the two opposing armies on the battlefield of Kurukṣetra, he refused to fight. In this way, age after age, the Personality of Godhead and His beloved confidential-servitor devotees bestow their unbounded mercy by dissipating the darkness of nescience of the people of the world. We could hardly have attained to transcendental knowledge if they had not bestowed such mercy upon us.
Sometimes the Personality of Godhead descends Himself; otherwise, He deputes His confidential servants to do this act of kindness. All the messiahs-saints who have come before or who will come in the future to preach the transcendental message of the kingdom of Godhead—are to be understood as the most confidential servants of the Personality of Godhead. Lord Jesus Christ appeared as the son of Godhead, Muhammad introduced himself as the servant of Godhead, and Lord Caitanya presented Himself as the devotee of Godhead. But whatever may be their identity, all such messiahs were of the same opinion about one thing. They preached unanimously that there is no peace and prosperity in this mortal world. All of them agreed that we have to go to a separate world, where peace and prosperity have their real being. We have to search out our eternal peace and prosperity in the kingdom of God, which is a place other than this mortal world. Even such messiahs and reformers as Lord Buddha—who did not accept the existence of Godhead and preached morality and ethics in the spirit of atheism—and Śaṅkarācārya—who did not accept the Personality of Godhead and preached morality and ethics in the spirit of pantheism—never preached that there is any possibility of attaining eternal peace and prosperity in this material world.
But at the present moment, the leaders of thought and the people in general have decided mistakenly that there is no other world except the one in which we live—that all peace and prosperity are available here, and that there is no existence of any other world wherein we can find a better position than here. According to such leaders, the material body is the actual self, understanding everything that pertains to the body constitutes self-realization, and we have no more duty than satisfying the senses of the body and maintaining it by all means. According to these leaders, God and philosophical approaches to Him are merely leisure pursuits or parlor games to exercise the brain. By such discussions, however, the world does not gain anything of substance.
So Marshal Arjuna pretended to display weakness, placing himself in the category of ordinary people who are illusioned in the material world. And by this action of his, Marshal Arjuna helped in the manifestation of Bhagavad-gītā from the transcendental lips of the Personality of Godhead. Whenever the Personality of Godhead descends to this mortal world, He is accompanied by His confidential servants. Marshal Arjuna is the eternal, confidential servant of the Personality of Godhead, Śrī Kṛṣṇa, and thus the philosophy of Bhagavad-gītā was taught to him directly for the benefit of the people in general.
Being an unalloyed devotee of the Personality of Godhead, Marshal Arjuna was able to discuss the transcendental philosophy of Bhagavad-gītā even on the battlefield of Kurukṣetra. We modern men have no time to get into the details of the philosophy of Bhagavad-gītā, even in the midst of our much more ordinary daily duties. But just to teach us, Marshal Arjuna tried to understand the philosophy of Bhagavad-gītā at a time when a moment was virtually impossible to spare. All this he did for the sake of people like us, and he fought the battle with full vigor once he had understood the philosophy of Bhagavad-gītā.