what comparison does the mariner make between himself, the water snakes, and the dead men in lines 236-239?

As he watches the water snakes he begins to perceive them differently, and suddenly their beauty becomes apparent to him for the first time. They are no longer beastly creatures to be condemned, but are creatures of God’s universe to be appreciated and loved. This new insight releases him from his invisible chains and he is able to offer a blessing for the water snakes. I suppose the comparisons made have to do with life and death, the beauty of life (even for a watersnake) and the inevibility of death.