Bed and Breakfast, Bed and Breakfast, Bed and Breakfast.
-- Narrator (The Landlady)

Importance: When Billy first arrives in Bath, he plans to stay at The Bell and Dragon. However, while walking the dark Bath streets, he encounters a small bed and breakfast with an inviting interior and a bewitching sign. This moment describes the impact the sign has on Billy. Indeed, the repetition of the phrase enacts its power over him. He feels incapable of resisting its allure, and is thus drawn into the landlady's trap. The moment reveals how impressionable Billy is, while simultaneously foreshadowing his fate at the story's end.

But really! You would think a widow was entitled to a bit of peace after all these years.
-- Narrator (William and Mary)

Importance: At the end of William's posthumous letter to his wife Mary, he includes a lengthy list of instructions for her. He reminds her that after he dies she is not to drink, eat sweets...