With the progression in human history, many people believed the transformation of spiritual faith that shifted the human perception of faith and removed the existence of Jesus Christ from the history. The decline in religious faithfulness has converted into an element of uncertainty for the believers. The poet Mathew Arnold pinpointed the Victorian era for the uncertain faithfulness as the first era and alienation of his self from the human beings and nature.
The poet started the poem with the short and simple line such as “the sea is calm” moving on, the poet created a momentum about the geography by casting of moonlight on the coast of France in the town of Dove. The writer told the audience about his location at the English Channel in England. The narrator used the enjambment to narrate the poem. The slow and gradual movement from line to line is beautiful and explicit. The use of a “tranquil bay” predicts the image of the dove cliff on the coast that gives the image of calmness in the dark. The author shifted the scene of calm and peace with a word “grating roar” compelling the reader to observe the difference in the scene of the bay. The pebbles of the shore transformed the granting sound of the beach into “tremulous cadence” or shaky rhythm of the ocean that hit with pebbles repeatedly. The end of the stanza cleared the picture of tranquil into an eternal view of sadness with the inbuilt sound of sorrow in it.
From the stanza,
Come to the window; sweet is the night-air!
Only, from the long line of spray
The poet used the symbol in the stanza as “night:” the night at the beginning of the stanza used to represent the calm and peace that later on shifted into the form of sadness and constant gloominess. 
Arnold found emptiness and isolation of human from God and from there human beings in the Victorian era that needed to resolve. He used the element of the union and companionship as the solution for removing the emotional emptiness and compensating the faith in God that every human lacks. He in his poem said,
“Ah, love, let us be true
To one another! For the world, which seems
To lie before us like a land of dreams,
… Hath neither joy, nor love, nor light.”
Love is the only solace in a world of the baffle. The bareness and uncertainty can light by indulging in companionship or relationship with another human as it is analogs to the love of God. The only way in the world of unfaithfulness is to rediscover yourself to connect to the god the only revival of god in the modern age. 
Arnold has explored the themes of love and fidelity over conflict. The poet used metaphor as “sea of faith” as the connotation of the problems of human life form birth to death and to symbolize the human existence into the liminal place. The sea of faith is a gesture of Arnold’s perception about the constructed image of a female body, feelings of longings and loss and the purposeless existence of a human in the world. From the lines,
“The Sea of Faith
Was once, too, at the full, and round earth’s shore
Lay like the folds of a bright girdle furl’d.”
The sea of faith represents the level of trust that the world had as equal to the level of the ocean. The hope has moved and declined to the level of fuddle. Arnold made the “the sea of faith” an important point to reflect the religious faith of the people that were most important to them and described its intensity with the high tide of the ocean. Here he used the word. “Bright girdle furled,” Arnold is comparing the metaphor with use of a simile that denotes the ocean of faith as beautiful belt surround the whole world at a point in time. The author explained the carefree and beautiful image of the human away from misery.
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.”
In the above lines, the poet shifts the point towards the decline of faith the faith that was wide at the beginning like the ocean is not taking high tide and is declining in its waves. Faith is retreating from the world’s faith is pulling away and now producing the sound of desolation. The image of the desolated land expressed with the use of imagery as “naked shrines” that are small pebbles left on an isolated and devastated beach. Arnold uses it to represent the loss of faith in God and its impact that is merely a desolation. 
From the explanation of the stanza, we can also extract that the faith has gone from the world and it can never get the pace, the tides can never be high, and there is not any hope of faith to get back to its normal stage.
“Sophocles long ago
Heard it on the Ægæan, and it brought
Into his mind the turbid ebb and flow
Of human misery.”
Arnold used allusion to create the link with the past to the famous Sophocles playwright on the Mediterranean Sea. The poet used the past reference to instigate the reader’s mind to think about humanity while observing sea. The author created the illusion of misery through Sophocles and trying to tell that the ebbs and flows of the ocean make him think about the misery of human. Another perspective of Arnold to draw a comparison with Sophocles is to bring the audience back in the time of ancient Greeks where the Sophocles used to write plays while analyzing the Aegean sea. That time of human misery has transformed into Arnold poetry as the decline of religion and faith among people in the modern world. 
The poem altogether is a blend of metaphors, symbols, and simile. The poet projected the perception of the religious faith of people especially in England that was strong once and sharply declined. The development of the poem shows the positive comparison of faith to the “sea.” Then the tide roaring sound that explained about the reality of the faith receding from the world. The poet added the reaction of nature to the human perception regarding tide, pebbles and desolated beach. The use of visual scenes in the form of ebbs and flow of the ocean tides represent the passage of time that adds the beauty of the melancholy. The reference of Sophocles is convincing in the form of allusion. 
On the other hand, it engraved with a message that faith in the divine power is important and losing it would affect the humanity. Arnold used the sound of faith retreat as “melancholy” that conveys the message. With faith, you cannot feel alone, but without faith, there would be isolation and uncertainty in the world.
Dover Beach. Dover Beach. n.d. http://doverbeachpoemanalysis.weebly.com/figurative-language.html.
Hopkins, Mathew Arnold, and John. “Reviving God: a study of Matthew Arnold and Gerard Manley Hopkins’ religious belief.” Laurann de Verteuil ’07, English Literature 99HL (2007). http://www.victorianweb.org/authors/arnold/deverteuil.html.
Shmoop. Dover’s Beach. n.d. https://www.shmoop.com/dover-beach/stanza-3-summary.html.
thanatassa. What is the effectiveness of the metaphor in stanza three in “Dover Beach”? n.d. https://www.enotes.com/homework-help/what-effectiveness-metaphor-stanza-three-dover-484033.