O scorcher of thy foes, those who have no faith in this dharma do not attain to Me, but return to the path of rebirth and death. (Gita Chapter IX verse 3).
Those who have no faith in this dharma, in this religion that teaches about the immortality of the Soul; those who believe that the body is all there is of man; those atheists who do not believe in any higher power (call it what you please); those who are sinful, unlawful and full of passion — they do not attain me when they pass out of this life. They return again and again to this world till they change their ways and beliefs.
We have seen that where our heart is and our thought, love and attachment are, there we go because our thoughts are the forerunners, and we have to follow them. Therefore those who do not believe in a life hereafter, who think that there is no soul whose welfare need give them the least concern, who think there is no absolute Being to aspire after — they come back to earth. For in this world all their hopes and thoughts are bound up. Of course there may be very good people who are out-and-out atheists. They do not get free from samsara, but they will be born on earth under favourable conditions; while atheists with evil tendencies will meet with miserable conditions when they return.
These three verses are, as it were, an introduction to prepare Arjuna for the doctrine that will now be expounded. By extolling the teaching Sri Krishna has aroused in him that curiosity and desire to know the Truth, which will enable him to listen till the very end with concentrated attention. It is only thus that this difficult and sublime subject can be comprehended.