A man sits by a ditch with a broken instrument and howls at a woman who isn't there to hear him. In four lines, Shelley sets up a small comic scene, and inside it a pointed idea: hatred makes bad art, and the person who sings it ends up exposing himself more than his target.
Everything starts with the title. A "hate-song" turns the love lyric upside down. The lute in the second line is the traditional instrument of the serenade, the thing a lover carries beneath a window. Here the setting is wrecked. The musician sits "by a ditch" instead of in a garden or under a balcony, and the lute is "old" and "cracked." The poem never explains the damage, but a cracked instrument can't produce a true note, and it's easy to read it as a picture of the singer's own spoiled spirit. Even before he opens his mouth, we expect the sound to be ugly.
The speaker names him only as "a hater." The inverted phrasing, "A hater he came," has the ring of an old ballad, but it also reduces the man to a single trait, as if hating were his whole job and identity. He has no name and no history, only an occupation. The woman is just as anonymous, "a woman that was a brute," and we never learn what she did. The poem withholds her side of the story and any evidence for the charge. That leaves us with only the singer's word, which is not a reliable witness.
The sound of the verse backs this up. The stanza alternates longer and shorter lines, four beats then three, the pattern of a folk ballad or nursery rhyme. That bouncy, sing-song movement sits oddly with the subject matter, and the mismatch is funny: a song of fury sounds like a jingle. The rhymes are uneven in a revealing way. "Lute" and "brute" make a clean, full rhyme, but "ditch" and "screech" only half-match, sharing their closing consonants while the vowels clash. Judging by the effect, it's tempting to hear that near-miss as a small musical flaw, a note slightly off, just as the song itself is meant to be.
The word choices do a lot of the comic work. "Screech" is a harsh, hissing word that leaves the idea of singing far behind, and the phrase "more of a screech" is wonderfully offhand. That "more of" sounds like a bystander quietly correcting the record, and it deflates the hater's dignity. "'Gainst" adds another layer. The clipped, archaic contraction fits the ballad mode, yet "against" also suggests a battle, so the singer treats his song as a weapon while we see only a noise from a ditch. Then there is "brute." It lands on the final beat of the poem and gets the last word, but it is an animal word, and the only brutish sound we have actually heard is the screech. The insult swings back toward the man who throws it. Even the pronoun matters: "a woman that was a brute" uses "that" where we might expect "who," which makes her sound more like a thing than a person, and that is exactly the attitude the poem invites us to distrust.
What does it all add up to? The central idea is that hatred and song don't mix. Music, in the tradition this poem borrows from, is meant to praise, woo or console. When it is turned to pure contempt, it breaks down into noise, and the instrument seems to break with it. The poem's humor is gentle but sharp. It doesn't say the woman is innocent, only that this is a poor way to accuse her.
The poem's significance lies partly in its compression. As it stands here, it is a tiny scene with a character, a setting, an object and a verdict, all in about twenty-five words. For readers who know Shelley from lofty pieces such as "To a Skylark," its mocking, almost cartoonish tone is a surprise. It shows how a few well-chosen words, a ballad rhythm and one imperfect rhyme can make a tiny satirical portrait of the kind of person who mistakes loudness for truth.