Once entered into the continuation of material existence is the very difficult to get out of it. And therefore the Supreme Personality of Godhead comes Himself, sends His bona fide representative, and leaves behind Him scriptures like Bhagavad-gita and Srimad-Bhagavatam so that these..., these living entities hovering in the darkness of nescience may take advantage of these instructions and saintly persons and spiritual master and get out of it. But unless there is mercy of the saintly persons or spiritual master or Krsna, it is not possible for the living entity to get out of this darkness of material existence by one's own endeavor.