As the poem begins, the speaker appears to be stepping into God's shoes, taking charge of one of the most important events in the Christian imagination: the Last Judgment, the day when the dead will rise from their graves and face God's justice. In an apostrophe to the "angels," the speaker kicks off the big event, also known as Judgment Day or the Apocalypse:
At the round earth's imagined corners, blow
Your trumpets, angels; [...]
The speaker is alluding to lines in the biblical Book of Revelation, a description of the Apocalypse in which angels are said to stand at the four corners of the earth. He's also making a clever point about how and where these events are taking place.
The speaker knows the earth is "round," a globe. Still, he beckons the angels to stand at its "imagined corners," corners it doesn't have. This mixture of the real and the "imagined" suggests that, in some sense, he's trying to reach beyond the limits of the known, everyday world—to imagine an event that will take place in this world, but also transform it in incomprehensible ways.
Perhaps that explains why he's putting himself in God's shoes here, too: issuing decrees, commanding the trumpets to sound. Imagining the coming Apocalypse, he's in a sense creating it, playing out his own end-of-the-world scenario.
However, the language he uses suggests he feels boggled by the sheer scale of the task. Even in the role of a commanding God, he can't fathom just how many souls will return from the dead on the fateful day. God proverbially sees the fall of every sparrow and can enumerate every single hair on every person's head. The speaker, by contrast, can only speak of "numberless infinities / Of souls," more souls than he can fit into his imagination. The pluralization of those "infinities" drives the point home: not just an infinity of souls, but infinite infinities.
Still, the speaker does his best within his limits, calling those "infinities" to "arise, arise" (with an insistent diacope rather like the blare of those angelic trumpets) and return to their "scattered bodies."
This poem is one of Donne's "Holy Sonnets," a 19-poem sequence in which he examined the mysteries and struggles of his Christian faith. The sonnet shape is compact and fairly strict:
- It uses 14 lines of iambic pentameter (that is, lines of five iambs, metrical feet with a da-DUM rhythm, as in "Your trum- | pets, an- | gels, and | arise, | arise").
- It also uses a set rhyme scheme. Here, the speaker uses the scheme of a Petrarchan sonnet, which divides into an eight-line introductory octave rhymed ABBA ABBA and a six-line closing sestet, here rhymed CDCDEE (though Petrarchan sestets can use any pattern of C, D, and E rhymes).
The rigorous demands of this form suits the speaker's task: to face the terror, grandeur, and hope of Judgment Day, trying to imagine what this final cosmic holiday will really mean.