Donne starts his prayer like a lawyer. "Thou hast made me, and shall thy work decay?" is a question that doubles as an accusation: if God is the maker, then the maker is responsible for the damage. The next line drops the argument for panic: "Repair me now, for now mine end doth haste." The repeated "now" shows how short of time the speaker feels. He talks to God less with reverence than with the urgency of someone who has just noticed how close the edge is.
The first eight lines are about movement and being stuck at once. "I run to death, and death meets me as fast" describes two runners closing on each other, so the collision comes sooner than either could manage alone. Yet the speaker is also frozen: "I dare not move my dim eyes any way," with "Despair behind, and death before." He is pinned between two fears. The pleasures of his life, meanwhile, have shrunk to "like yesterday," a flat, deflating simile that gives them no weight or warmth. Weight comes in only with sin, which makes his "feeble flesh" waste away and "towards hell doth weigh." Sin works here like gravity, a physical pull downward that he cannot resist.
The form follows this pressure. The octave rhymes *abba abba*, as in the Italian sonnet, and the sounds suit the sense. The *b* rhymes (haste, fast, cast, waste) are short and clipped, and they make the speaker sound hurried and out of breath. The *a* rhymes (decay, yesterday, way, weigh) are long and open, like things slipping away. The sestet rhymes *cdcd* and then closes on an English-style couplet, so the poem mixes two sonnet traditions. The rhythm is iambic pentameter, but Donne keeps breaking it with commas, as in "Repair me now, for now…" and "Despair behind, and death before doth cast / Such terror." The sentence spills over the line break just as terror spills over the speaker. The result sounds like someone speaking, stumbling and starting again, and not like a polished recitation.
The turn comes at "Only thou art above," and the imagery moves from falling to rising. Even here the speaker is not confident. He can look up only "by thy leave," as though he needs permission just to turn his eyes toward God. He admits that when he does, "I rise again," but "our old subtle foe" (the poem's way of naming the devil, judging by the context of temptation and hell) undoes it, so that "not one hour myself I can sustain." His hope never lasts an hour, and he cannot maintain it himself.
The couplet gathers everything into two images. "Thy grace may wing me" turns the heavy, sinking body into something that could fly. Then comes the surprise: "And thou like adamant draw mine iron heart." In Donne's time "adamant" could mean a lodestone, a magnet, as well as an unbreakable stone, and both senses work. God is the magnet, and the heart is iron, hard and cold and unable to move toward God by itself. The word also hints at something stubborn in both of them: the heart refuses to bend, and only something immovable enough can pull it. Notice too the grammar. The speaker is the object of every verb, "wing me," "draw mine iron heart," and he does nothing himself. The cautious "may" also keeps the ending a hope, not a promise.
That honesty is much of what makes the poem matter. A reader might expect a devout poem to end in calm assurance. In contrast to the defiance of "Death, be not proud," where the speaker mocks death, this speaker is afraid of it and admits that even his faith needs outside help to survive an hour. The poem argues, bargains, panics and pleads, all in fourteen lines, and it makes the fear believable by giving it physical form: running, weighing, rising, being pulled. Four centuries later, the sense of a mind trying to reason its way out of terror and ending up with nothing but a request still feels recognisable.