Explication of "At the round earth's imagin'd corners, blow"

Rhyme scheme: abba abba cdcd ee
Rhythm: iambic pentameter
Form: Italian sonnet

John Donne's lyrical sonnet "At the round earth's imagin'd corners, blow" expresses a persona's desire for spiritual redemption.  Borrowing conventions from both the Italian and the English sonnet forms, Donne divides this poem into three sections.  In the first section, an octave that is rhymed abba abba and that is clearly modeled on the conventional octave of the Italian sonnet, the persona calls for the Last Judgment.  In doing so, he makes several allusions to the Revelation of St. John the Divine from the New Testament.  For example, he refers to trumpets, war, and woe, and he suggests that humans will "behold God."  This section also contains an allusion to the Great Flood, which is described in the Book of Genesis in the Old Testament.  Because they call on knowledge that many readers already have, these allusions help to engage readers and make them appreciate the persona's thinking about redemption.  The persona seems eager to achieve redemption--so eager, in fact, that he wants to see the earth end so that he can attain this goal.  A number of formal features complement this message.  For instance, the spondee "round earth's" packs extra force in line 1, giving the poem's opening a sense of urgency.  This urgency is suggested also by the persona's use of the imperative mood; indeed, three of the verbs in this mood attract special attention because they appear at the ends of lines: "blow" (1), "arise" (2), and "go" (4).  In the poem's second division, clearly marked with the word "But" at the beginning of line 9, the persona changes his mind and asks God to delay the judgment, saying "But let them sleep, Lord, and me mourn a space."  The alliteration of the "m" sound gives this line a less urgent, more somber tone.  The persona seems to have become calmer and more introspective.  Having given vent to his bottled up excitement about the need for redemption in the octave, he is able to reason objectively and decides that he has been impetuous.  In lines 10-11, he says: "For if above all these my sins abound , / 'Tis late to ask abundance of thy grace," showing that he realizes that the Last Judgment could leave him without God's redemption if his sins are too great.   Finally, the poem's last section, a couplet modeled after the concluding couplet of the English sonnet, provides the persona's own judgment of what he needs to do: he needs to learn to repent and thus earn God's pardon for his sins.  With the words "Teach me how to repent; for that's as good / As if thou'hadst seal'd my pardon with thy blood," the persona suggests that earning his pardon through his own repentance is equal to receiving it through God's grace.  This conclusion reflects the focus on the individual we often see in Renaissance literature.  Rather than waiting for God to do the work for him, this persona is taking action to save his own soul.