The first word of "Sympathy" is "Therefore," an odd way to begin, since it suggests an argument is already under way and we have walked in halfway through. The poem hands us the conclusion first ("I dare reveal my private woe") and gives the reasoning a few lines later, in the sentence that works as its hinge: "For this I know, / That even as I am, thou also art." Emma Lazarus's idea is simple but bold. Because every heart is flawed, the speaker can afford to be honest about hers, and that honesty, not perfection, is what links one stranger to another.
The confession is carefully worded. The "secret blots of my imperfect heart" are literally ink stains, so the heart becomes a page with its mistakes left showing. The speaker then rules out four temptations in two quick phrases: she will not "shrink or swell mine own desert, / Nor beautify nor hide." "Desert" here means what one deserves, so she refuses both false modesty and boasting. "Beautify" and "hide" cover the two ways people usually handle a fault, which are to dress it up or to bury it. The verbs are blunt, and the lines themselves are plain, which suits a poem about plainness.
Formally, this is a sonnet in iambic pentameter, and the steady rhythm keeps the tone calm, like someone speaking quietly rather than exclaiming. The octave uses only two rhyme sounds in the pattern ABBABAAB. Four of its lines end on the long "o" of "woe," "know," "go" and "low," which tolls through the first half like a soft bell. The other sound links "heart," "art" and "apart." Taken together, those words trace the poem's argument: the heart is imperfect, "thou also art" the same, and so neither of us need be apart. ("Desert" joins this group only as a loose chime with "heart.") The sestet rhymes CDCDEE, ending in a couplet, so the poem mixes an octave-and-sestet shape with a closing snap.
The most interesting structural move is a change of voice. The quotation mark opens in the middle of line 8, and from there the words belong to the imagined reader, not the poet. Where a sonnet usually pauses for its turn, the sentence runs straight over the line break: "not I apart / Must suffer." The poem refuses to stop at the very point where it denies isolation. Earlier, the poet predicts that this reader "past heroic forms unmoved shalt go." "Forms" suggests statues or idealised portraits, though that is an inference from the word. The reader walks past such grand figures to "pause and bide with me, to whisper low." Moral grandeur leaves her cold, and a flawed human being makes her stop.
In the reader's whispered speech, the language of struggle is modest. "Suffer, struggle, conquer day by day" makes victory something small and repeated, and "hourly deliverance" shrinks the timescale further. The religious vocabulary of "cross," "bosom-sin" and "pray" gives the private fault real weight, and "bosom-sin" suggests a failing kept close to the chest. "This my rose, my thorn" fits beauty and pain into one phrase, as though the two cannot be separated. The reader also says the cross is "by strangers borne." She sees her own burden carried by someone she does not know, and the poem treats that moment as recognition.
The closing couplet shifts into the third person: "This woman my soul's need can understand, / Stretching o'er silent gulfs her sister hand." The reader now talks about the poet as if looking at her from outside. "Silent gulfs" is a wide, empty image of how little people say about their real troubles. "Sister hand" bridges it, and the rhyme of "understand" with "hand" fuses comprehension and touch.
What makes the poem lasting is that it does what it describes. It could have argued for sympathy in the abstract, but it performs it: the speaker uncovers a flaw, and the poem imagines a stranger answering with a hand. Its quiet claim is that literature matters less for heroic forms than for the shared admission that nobody suffers alone.