The Ocean of Birth and Death
Imagine yourself adrift in the midst of the vast ocean. Even if you were the world's greatest swimmer you would eventually drown unless someone came to your rescue. The material world is compared to a vast ocean: an ocean of birth and death. Souls trapped in this world cannot free themselves from the continuing cycle of birth and death.
But they can be freed by the process of yoga. Yoga means union with the Supreme. This is the stage beyond all anxieties. Thus the soul, perfectly linked with the Supreme Soul, through devotion, is at once rescued from repeated birth and and death by the mercy of Krishna.