One of the few hazards of being an English professor is that when a friend or relative gets married, they might invite you to read a love poem at the wedding. It’s an honor to be asked, of course, but I’ve also found it surprisingly difficult to choose the right poem. The problem is that many of the greatest love poems are bad material for weddings. No wonder countless best men, maids of honor and plainclothes officiants have found it so difficult to pick something good for the big day.

The need for poems at weddings is not new. In fact, there’s a special term for a wedding poem: epithalamium. This genre reaches all the way back to ancient Greece, but the most famous epithalamia do not work well at modern weddings. The earliest examples, such as those by Sappho and Catullus , make distracting references to ancient gods — including to Hymen, the Greek god of marriage. Pro tip: Select a poem that will not require you to say “hymen” aloud during the ceremony. Other notable epithalamia, from Edmund Spenser to E. E. Cummings , are just too long and obtuse to do the trick. Spenser, writing in 1594, begins with an appeal to the muses, whom he calls “Ye learned sisters,” and goes on for 365 lines. Cummings, in 1916, starts by describing the “quivering continual thighs” of “thou aged unreluctant earth,” which is just as weird.

Sex, as Cummings’s evocative phrasing suggests, is the most obvious problem. The greatest love poems are full of excited, entangled bodies. But given the audience at most weddings, it’s best to avoid anything too explicit. Keeping it strictly PG rules out lots of wonderful love poems. Some of my personal favorites get a crucial bit of spice from erotic details. In “Recreation,” Audre Lorde writes beautifully of how “you create me against your thighs.” Another favorite of mine, Bernadette Mayer’s “First Turn to Me,” is even more openly, gorgeously erotic: “You arrive at night inspired and drunk, / there is no reason for our clothes.” Poems like this speak deep truths about the physical aspects of love, but kinky is just the wrong tone for the parents getting weepy in the front row.

The next problem is even trickier: While good poems tend to sing with the help of specific, vivid details, these grace notes rarely match well with the couple getting hitched. Maybe the woman in an otherwise ideal poem is a blonde, but your friend the bride is a brunette. Maybe it’s a wonderful poem that happens to mention God, which disqualifies it for a secular wedding. Elizabeth Barrett Browning’s famous Sonnet 43 begins “How do I love thee?” and answers with soaring claims of devotion: “I love thee to the depth and breadth and height / my soul can reach,” which has a conveniently generic resonance. But it also says that her love will continue in heaven “if God choose.” Alternately, perhaps the poem you like is a bit, well, hetero for the two men about to take their vows.

Far less important details can still distract. I was at a friend’s wedding years ago, and the mention of cigarettes in “Resignation,” an excellent poem by Nikki Giovanni, left me wondering whether the groom had quit. Potential wedding poems face the challenge of including just enough detail but not too much. Some good ones about love in general, such as Rilke’s “The Lovers,” contain so few specifics that they might apply to any couple, but they often sound rather vague for the same reason.

Some of the most famous love poems have become hard to enjoy because they treat women as mere sex objects. Robert Herrick begins one poem, “Display thy breasts, my Julia.” I will not cite more recent examples, which are quite a bit more lewd, but descriptions of women also appear in some of the very best love poems, including one of my all-time favorites, Theodore Roethke’s “I Knew a Woman.” Even when a poem does not seem outwardly sexist, it might sound lopsided at a wedding because it says a lot about the woman and almost nothing about the man.

Many love poems seem perfect for a wedding until you actually pay attention to what they say. Poets like to get clever, so backhanded compliments abound. One of Shakespeare’s most famous love sonnets, Number 130 , basically declares, “She’s ugly and has bad breath, but I love her anyway.” Number 18 — which begins, “Shall I compare thee to a summer’s day?” — leads, in effect, to the conclusion, “You’re pretty, but you’re going to die, and this poem will live forever.” Neither will please an attentive bride. Dorothy Parker was the modern mistress of romance with a poison pill. Her “Grande Passion ” shamelessly emphasizes physical beauty: “If you should break your beauteous nose, / My love would perish, I suppose; / . . . But lose, my love, your soul and sense — / I should not know the difference.”

A related, surprisingly common problem is that lots of good love poems end with a mention of death. The third of Adrienne Rich’s “Twenty-One Love Poems” would do nicely for those marrying later in life, except it concludes by declaring that “each of us must help the other die.” Likewise, “death” is the last word of the Browning sonnet mentioned above. I think the standard phrase “till death do us part” is more than enough talk of mortality on the happy day. In class, I try to show students the rewards of reading attentively. At the altar, a poem full of pretty phrases will backfire if its deeper meaning is too grim.

The most interesting difficulty with wedding poems involves what academics call “address,” a lyric’s ability to construct an individual to whom its message is directed. Often a love poem feels most powerful when it speaks directly to “you,” the beloved. But that power can go awry in public settings. The technique is very common, appearing in some of the oldest love poems — among them, Sappho’s Fragment 31, which paradoxically declares, in Anne Carson’s translation, “for when I look at you, even a moment, no speaking is left in me.” If you’re writing a poem to seduce someone, then calling to “you” in verse can remind the person that you wrote those lines just for them. (Trust me, it works better than flowers.) Even if you’re not a poet, when you read poetry aloud you take the place of the “speaker,” the one expressing these feelings. As the critic Helen Vendler puts it, a lyric poem gives “its reader a script to say.” When one reads a poet’s words, Vendler tells us, “one is to utter them as one’s own words.”

This all works fine in private. When I read Frank O’Hara’s poignant “To the Harbormaster ” aloud to my partner, I get to be the speaker, and it’s obvious whom I mean to address when I recite, “To / you I offer my hull and the tattered cordage / of my will.” My address to “you” sweeps us both up in the poem. At a wedding, however, the effects of address can get dangerously slippery. Fragment 31, for example, describes a scene of romantic jealousy, one in which the poet’s beloved is caught in dialogue with another man. Read the lines aloud, and you risk giving the impression that your own “tongue breaks and thin / fire is racing under skin” for one member of the couple or the other.

Or, say your best friend invites you to read a poem at her wedding, and you select “Variation on the Word Sleep,” a real gem by Margaret Atwood. On the big day, you begin reading: “I would like to watch you sleeping . . .” Now you’re a creep who wants to observe the happy couple in bed. Or maybe it’s your brother’s wedding, and thanks to Pablo Neruda you find yourself telling him, “I love you as one loves certain obscure things, / secretly, between the shadow and the soul.” Nobody wants to hear about your secret love for your brother. Unless you are the one getting married, you might want to skip poems that address a beloved “you.” Too often this means avoiding those that speak in the actual language of love, instead of just evoking cliches about the abstract idea of it.

As those who have tried to pick the right poem for a wedding can confirm, these are just a few of the difficulties involved. Of course, if you really cannot find the perfect verse for the big day, you could always try writing your own. But believe me, that’s not any easier.

Twitter: @seth_perlow

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