So Lord Kṛṣṇa, He descends, yadā yadā hi dharmasya glānir bhavati (BG 4.7), just to establish the real purpose of life. When man forgets the real purpose of life, the mission of human form of life, then it is called dharmasya glāniḥ, the disturbance of the occupation of human being. So in that circumstances, out of many, many human being, who awakens, one who awakens the spirit of understanding his position, for him this Bhagavad-gītā is spoken. We are just like swallowed by the tigress of nescience, and Lord, being causelessly merciful upon the living entities, especially for the human being, He spoke Bhagavad-gītā, making His friend Arjuna as the student.