This will kill him, the old man thought. He can’t do this forever. But four hours later the fish was still swimming steadily out to sea, towing the skiff, and the old man was still braced solidly with the line across his back.

Santiago reacts to the marlin taking hold of the hook and beginning to pull the skiff. Based on Santiago’s experiences catching fish in the past, he does not believe a fish can sustain such strength for long. However, the marlin refuses to give up and seems willing to fight Santiago’s attempts to catch him for as long as he can.

There are two more hours before the sun sets and maybe he will come up before that. If he doesn’t maybe he will come up with the moon. If he does not do that maybe he will come up with the sunrise.

As the day comes to an end on Santiago’s first day at sea, he speculates on how long the fish can stay in the water on the hook. Santiago has already been waiting to reel the fish in for much longer than he has in the past, and here he wonders if he will be able to reel in the fish in the evening, at night, or even the next morning. He will wait as long as he needs to for the fish to give up.

“Fish,” he said softly, aloud, “I’ll stay with you until I am dead.

Santiago speaks here to the marlin, but also to himself, after the marlin lurches and causes Santiago to cut his face on the first night at sea. Rather than considering giving up and going home, Santiago vows to reel in the marlin or die. He no longer feels concerned with his own safety and health, but he remains determined to bring home the marlin to prove that his unlucky fishing streak has ended.

I must get him alongside this time, he thought. I am not good for many more turns. Yes you are, he told himself. You’re good for ever.

As the marlin circles the skiff, Santiago thinks that he cannot go on much longer and needs to get the marlin next to the boat soon. He quickly corrects his pessimistic thinking with the statement that he can go on forever. Even though Santiago has been contending with the marlin for days and feels weak, he makes sure that his thoughts remain positive and hopeful so that he can accomplish his mission, and he does not allow himself to give up.