What does the quoted passage from "Dover Beach" mean in the context of the poem?

"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 help for pain."

This quotation is from the final stanza of Matthew Arnold's poem “Dover Beach.” The speaker has been standing at a window observing the sea and cliffs. He remarks, “The sea is calm tonight / The tide is full, the moon lies fair / Upon the straits...” (lines 1–3). He invites his love to join him at the window to smell the sweet night air and watch and listen as the sea spray crashes into the “moon-blanched land” (line 8).

However, as the two stand at the window, the speaker notices something else, “The eternal note of sadness” in the sound of the sea (line 14). His mind turns to metaphor, and he recalls how Sophocles looked at the sea and found an image of “the turbid ebb and flow / Of human misery” (lines 17–18). The speaker then develops his own metaphor. For him, the sea represents the “Sea of Faith” (line 21) that once spread broadly across the world but is now retreating and leaving behind only the “naked shingles of the world” (line 28).

Without faith, there is little left of value in the world, the speaker laments in the final stanza. What seems like a beautiful “land of dreams” (line 31) is only an impersonal material realm with no joy or love, no light or peace, no certitude or “help for pain” (line 34). Without faith, the world loses its meaning. Without faith, the beauty of the world is an empty thing, and the world fills with darkness, ignorance, and “confused alarms of struggle and flight” (line 36). Without faith, the speaker must turn to the only solace he can find: his love. He pleads with her that they might remain true to each other, for in a world emptied of faith and meaning, all they have left is their love.

Indeed, “Dover Beach” approaches despair in its final stanza, yet the speaker, even as he mourns the loss of faith in the world, emphasizes how indispensable that virtue is if those who live in the world will find any joy, love, light, certitude, peace, or help in times of trouble.

What is the meaning of the quoted passage in the context of "Dover Beach"?

"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 help for pain."

The immediate context of the poem is a scene in which a young man, possibly on his honeymoon (Arnold honeymooned in 1851 at Dover Beach) gazes out the window of his hotel room at night. He calls his wife to stand beside him because the night air smells and feels "sweet." In the moonlight, he sees the sea, which is calm and tranquil, and hears the "grating roar" of the waves hitting the pebbles on the shore. The sound is sad to him.

He turns inward when he says that Sophocles, the tragic playwright of ancient Greece, was also made sad from the sound of the waves, then goes on to muse on the "Sea of Faith" that once banded the world brightly, but now is receding, leaving only a "melancholy, long, withdrawing roar." He rouses himself from his sad, fearful thoughts to speak to his wife. He says they have to remain true to one another and cling together because the world is a dark, fearful place with

really neither joy, nor love, nor light,

Nor certitude, nor peace, nor help for pain

And we are here as on a darkling plain