"But you might as well bid a man struggling in the water, rest within arm's length of the shore!" is a powerful metaphor highlighting the urgency and difficulty of achieving a goal when one is close yet still out of reach. It emphasizes the challenge of perseverance, even when the destination seems near, but obstacles remain.

The quote continues with the sentiment that the person must reach the shore themselves before they can rest, reflecting determination and personal effort. It suggests that true relief or success comes only through individual striving and persistence, despite the struggles faced along the way.