So your family — your uncle, in fact — is throwing a Christmas party, so big it’s a public event. Halfway through, a guest shows up late. He was uninvited, no one has ever seen him before, and he is rather rude. He is also green — not just his clothes, and not green from drunkenness, but a bright, vivid green.

What do you do? Make a life-and-death bet with him, of course, to be fulfilled in a week and a year — New Year’s Day of the year after next.

Sir Gawain and the Green Knight is a medieval poem. The author is as unknown as the green guest himself. His poem can be read, to yourself or aloud, in one long sitting, or broken up between parts two and three. The form is unusual; irregular stanzas of four-beat alliterating lines, capped by five-line bits of rhyme. The language is Middle English, but of a northern dialect that got shunted aside by the London dialect of Geoffrey Chaucer. That is why Chaucer can still be hacked through by a layman with the help of notes. Sir Gawain requires translation.

I have read a number of modern English versions over the years: by Tolkien, Simon Armitage, W.S. Merwin (poor Merwin, who was a vegan Buddhist, compelled to render the long hunts in part three). But my favorite, unsurprisingly, is the first one I read, by Burton Raffel (d. 2015). I reread it in the paperback I bought in high school. Raffel uses more enjambment than the other translators and, I imagine, the original, but it assists him in one of his best features, the propulsive forward motion.

There will be no spoilers here. Suffice it to say that Sir Gawain offers suspense, weirdness, sexiness, and moral quandaries. Raffel’s introduction cautioned his readers to enjoy the poem’s ironies without trying to overinterpret it, especially not the greenness of the anti-hero. But let me take a swing. Green in the middle of winter is life, and every life is a series of bets. We take them, like Gawain, and like him, do the best we can.