Q: How could have Sri Krishna told 700 verses of Gita on the Battlefield, making Arjuna understand all the secrets of life? When people spent years and years studying Gita, how could Sri Krishna possibly convey the entire meaning of Gita in the battle field?
A: Arjuna was a learned person, with knowledge of many Sastras. Currently, he was deluded — not able to decide what is right and what is wrong. Sri Krishna might have inspired Arjuna through few words and that would have been enough to convey the ideas. All the ideas in Gita are taken from Upanishads / Vedas. It is all combined and conveyed to Arjuna in a way he could understand.
During that time of Gita, Arjuna and Krishna were in a totally different dimension. You could say that “the bandwidth and connectivity were very high.” Between a disciple and Guru, the connection should be like that. It was in total Love. That Love can transcend time. Later after the war when Arjuna asked Sri Krishna to repeat the Gita again, Sri Krishna says that he was in a different mood at that time, and he is not now, so he can’t repeat.
When one sits with his/her girlfriend or boyfriend, hours seem to pass in seconds!. In Love one transcends time. Arjuna’s devotion to Sri Krishna could have made it possible for Sri Krishna to convey entire Gita to Arjuna. But, the question should be whether Gita is helpful to our life. We need only to be interested in the ideas discussed here.
Note: The original Mahabharata, as written by Jaya had 24,000 slokas and later expanded to 1,24,000.