Lessons from Srimad Bhagavad Purana

When he was created man was given the power of discrimination and he was given a good intellect. These should help him to set his thoughts on the Brahman. After so many births, far inferior to the human status, after passing through the worm state and then reptile state and then animal state, man is granted the privilege of having a human form and a human mind and a human intellect. Why? So that he can use them properly. This body should be kept alive very carefully for but one purpose: to attain salvation because that is the only reason why we are given this form.

Live in the world of men without being attached to anyone or anything. Set your thoughts on me (Krishna). Act in the world without any desire to please yourself.

Concentration is essential if one desire to attain one-ness with the Paramatman.
Srimad Bhagavad Purana