In this poem, Frost is rejecting walls and barriers that separate people from each other. He is for love, intimacy and brotherhood between people. He considers the gaps in the wall that was made by nature as positive things, because they admit people to pass through them" abreast ", so they can be able to face each other and become closer. This stands in contrast with the wall which functions as a separator of people, to the extent that when the persona and his neighbor were mending it, they did not want to face each other; instead, they preferred to "stay where you are until our backs are turned ".
This rejection of the wall is further emphasized by the use of pun in the phrase "spring mending time ". The two neighbors meet at the time of spring in order to mend the wall. However, since spring is the time of joy and love, so nature destroys the wall in order for spring to mend the hearts of the people separated behind this wall.
The refusal of the wall can be also interpreted in terms of breaking this tradition, since there is no logical reason in keeping it. Thus, the neighbor who insists on sticking to tradition, is portrayed as an "old-stone savage" who "moves in darkness" of his ignorance and stubbornness. "He will not go behind his father's saying ", and he blindly repeats this outdated cliché: "Good fences make good neighbors ". This cliché represents a contrast that doesn't make sense. For good neighbors are made by habitual communication and closeness, not by being completely isolated from each other, especially by " good fences " which in this case can never be considered as good.
The wall itself hides under it "the frozen ground-swell" which symbolizes something horrible beneath the wall. In order for this thing to vanish, the wall has to be removed. This wall is meant for the protection of the weakest, so it hides under it the weakness of human beings.
"Frozen" here is contrasted with the "sun" that spreads light and beauty over the place, when the "upper boulders" of the fence are split. Even the title of the poem has a paradoxical meaning. The "wall" stands for the separation and isolation of people, while "mending" stands for communication and love between people.
Since Frost is calling for breaking traditions in this poem, therefore he wrote it in an untraditional blank verse. He started the poem with a monologue declaring that" Something there is that doesn't love a wall". Then moved to action, describing the destruction of the wall by the" frozen ground-swell"," the work of hunters", the dogs and rabbits. Then he used a dialogue between the persona and his neighbor while the mending of the wall, discussing their ideas about it. In the end, it turns out to be a wise and beautiful conversation.
Though he used the form of blank verse, which has no rhyme scheme, the poem is full of internal rhyme instead. The repetition of several phrases achieves this, such as: "seen the made/ heard them made", " set the wall between us/ keep the wall between us to show marks, " where there are cows/ here there are no cows" and " walling in/ walling out". There is also the use of consonance in some words such as: "hand/armed "and "moves/seems ".
In short, Frost succeeded in delivering his message, in making us think about the barriers that hinder humankind from communicating. He got his message delivered subtly and in a beautiful way either by his ideas, questions, and symbols or by the easy conversational form that he used in his poem.
