Death, be not proud, though some have called thee
Mighty and dreadful, for thou art not so;
For those whom thou think'st thou dost overthrow
Die not, poor Death, nor yet canst thou kill me.

The speaker opens the poem with these lines, which establish their address to a personified version of Death. The speaker aims to cut Death down to size by insisting that, however “mighty and dreadful” it may seem, Death lacks absolute power over life. The speaker makes this claim largely through negation—that is, through their insistent use of the word “not.” But the speaker adds rhetorical force in other ways. Consider the third line, which is sonically striking for the way it features repeated TH sounds: “For those whom thou think'st thou dost overthrow.” The line is also notable for the slightly odd way its use of iambic rhythm places double emphasis on the word “thou”: “For those / whom thou / think'st thou / dost o- / ver-throw.” Though slightly awkward, the speaker’s stress on the word “thou” emphasizes the informality of their address to Death. In Donne’s time, “thou” was the familiar and informal version of the second-person pronoun. Finally, it’s worth noting a certain irony in the speaker’s command that Death “be not proud.” Pride famously ranks among the so-called “Seven Deadly Sins.” The speaker’s command therefore has an ironic quality, cheekily cautioning Death against itself committing a deadly sin.

From rest and sleep, which but thy pictures be,
Much pleasure; then from thee much more must flow

In lines 5–6, the speaker draws a parallel between Death and sleep. The speaker symbolically links Death to sleep as part of their overall project of refuting Death’s power over life. In this case, the speaker refutes Death’s power by suggesting that “rest and sleep” are “pictures” of dying—that is, they are essentially imitations of what dying will be like. And since rest and sleep are both pleasurable activities, the speaker concludes that the experience of dying will be even more enjoyable: “from thee much more [pleasure] must flow.” By drawing out this symbolic link, the speaker effectively strips Death of its terror and presents it as something ultimately desirable.

Thou art slave to fate, chance, kings, and desperate men,
And dost with poison, war, and sickness dwell
And poppy or charms can make us sleep as well
And better than thy stroke; why swell'st thou then?

In the third quatrain (lines 9–12), the speaker begins by introducing a new reason to reject Death’s power. Essentially, the speaker claims that Death lacks its own agency and is instead a “slave” to abstract entities like “fate” and “chance.” Even more humiliating for a metaphysical figure, Death must also serve at the command of “kings” and “desperate men.” In other words, Death is an agent of other, more powerful forces. For this reason, it is better situated among despicable things like “poison, war, and sickness.” After making this point, the speaker briefly returns to the link they made earlier between Death and sleep. In the third line, they attempt to deepen Death’s humiliation by claiming that “charms” like opium (which is made from “poppy”) do an even better job that Death of putting people to sleep. This final claim occasions the speaker’s return to the point they made in the poem’s opening line. There, the speaker commanded Death to avoid pride. Now, after pointing out many of Death’s shortcomings, the speaker circles back to the question of pride and pointedly inquires: “why swell’st thou”?

One short sleep past, we wake eternally
And death shall be no more; Death, thou shalt die.

In the couplet at the sonnet’s end (lines 13–14), the speaker makes a logical leap to arrive at their shocking conclusion. If it’s the case that Death is little more than a version of sleep, then it’s reasonable to assert that Death isn’t final. Just as we wake after sleeping, it must be the case that after Death “we wake eternally.” Essentially, the speaker is asserting the Christian belief that there is life after Death. But the speaker drives this point home with a paradoxical flourish. Instead of simply saying that life trumps Death, the speaker claims that in the afterlife, “death shall be no more.” In other words, Death itself “shalt die,” and mortality turns out to be, paradoxically, mortal.