Can someone help please

In this excerpt from "dover beach" by matthew arnold, which two lines or sets of lines suggest that the speaker has undergone a loss of faith? the sea of faith was once, too, at the full, and round earth's shore lay like the folds of a bright girdle furled. but now i only hear its melancholy, long, withdrawing roar, retreating, to the breath of the night-wind, down the vast edges drear and naked shingles of the world. ah, love, let us be true to one another! for the world, which seems to lie before us like a land of dreams, so various, so beautiful, so new, hath really neither joy, nor love, nor light, nor certitude, nor peace, nor for pain; and we are here as on a darkling plain swept with confused alarms of struggle and flight, where ignorant armies clash by night.

Read the excerpt from how the grimm brothers saved the fairy tale. which idea does the author develop with the text example cited in the excerpt ?

Hi brothers and sisters may you tell me the answer of question ?