"Tyaktva deham punar janma naiti mam eti kaunteya [Bg. 4.9]. The formula is there. Krsna says, janma karma me divyam yo janati tattvatah. Simply if you try to understand what is Krsna, divyam. They are all divine, transcendental. Krsna's activities, Krsna's appearance, Krsna's worship, Krsna's temple, Krsna's glories -- everything transcendental. So if one understands these things or tries to understand, even he does not understand, tries to understand, then he becomes liberated from this process of birth and death. Krsna says. So become very serious to understand Krsna and remain in Krsna consciousness. Then this problem, birth, death, old age and disease will be solved, automatically, very easily. There will be no problem.
That is the function of the human life, to understand that "I am eternal." Krsna says that "In the past we existed, in the present we are existing, and in the future we shall continue to exist." Then why I have got this type of body by which I am actually, not actually, superficially I am not existing. So this is the problem. A dhira means a sober man will think of this problem, that "I want to live. Why death takes place? I want to live very healthy life. Why disease comes? I don't want to become old man. Why old age comes?" Janma-mrtyu-jara-vyadhi [Bg. 13.9]. These are the problems. So solve this problem simply by taking to Krsna consciousness, simply by understanding Krsna. And for understand Krsna, the Bhagavad-gita is there, so nicely explained."
(Srila Prabhupada lecture, September 19, 1973)