Lord Krishna is considered to be the eighth avatar of Lord Vishnu. His recitations to Arjun on the battlefields of Mahabharata formed the Bhagwad Gita.
The main objective of Gitaa is to help people struggling in the darkness of ignorance cross the ocean of transmigration and reach the spiritual shore of liberation while living and working in the society. The central teaching of the Gita is the attainment of freedom from the bondage of life by doing one's duty.

When one realizes Him by His grace, the knots of ignorance are loosened, all doubts and confusion are dispelled, and all Karma is exhausted 

http// lordkrishna.info