Ursula's Additional Question

Why does Pip so greatly emphasize the cowardice that led to his possible insanity? I get that feeling that this is a key factor in his otherworldly omnipotence and wisdom, but cannot quite discern its express meaning/ symbolic importance.

Ursula's Assorted Questions from Ch. 36-42

1. What is the importance of digestion? Melville constantly brings it up, but for what purpose?

2.  In Ahab's fiery speech to the crew in Ch. 36 on pages 141 and 142 the word "that" is italicized and emphasized. What does it refer to?