The rhyme scheme of this poem is ABBA CDDC EFEF GG, which is the English sonnet. It consists of three quatrains and one rhyming couplet at the end.
Thou hast made me, and shall thy work decay?
Repair me now, for now mine end doth haste;
I run to death, and death meets me as fast,
And all my pleasures are like yesterday. (lines 1-4)
The narrator is asking God if He is just going to let His work go to waste. He demands that God fix him quickly, because death is upon him. He is scared that God will not absolve his sins before he dies, and he will then not be able to enter into heaven. In line four, he is describing the moment where your life flashes before your eyes when you are sure that you are going to die.
I dare not move my dim eyes any way,
Despair behind, and death before doth cast
Such terror, and my feeble flesh doth waste
By sin in it, which it towards hell doth weigh. (5-8)
He does not want to move his eyes away from God, because he is scared that the devil will take that opportunity to damn him to an eternity in hell. The sins that he has amounted during the course of his life scares him just as much as his impending death; if he is found unworthy of God's love, he will have to suffer the consequences. His sins are rotting away his flesh, and they are so heavy that he believes he is slowing sinking into hell.
Only thou art above, and when towards thee
By thy leave I can look, I rise again;
But our old subtle foe so tempteth me
That not one hour myself I can sustain. (9-12)
God is the only one who matters now; his last judgment will decide whether the narrator has done enough to get into heaven. It is by God's grace that he will rise up into heaven; so he will look up to heaven in hopes that he will soon be going there. The devil is still there trying to tempt the narrator, and if God doesn't take him soon then his soul will be going with the devil.
And thou like adamant draw mine iron heart. (13-14)
These last two lines are the sonnets rhyming couplet, which serve to sum up the entire poem. He tells God that His grace will give him the wings to escape the clutches of the devil. The last line is an analogy: God is like a giant magnet that attracts the narrator's iron heart.
"John Donne." The Norton Anthology of English Literature: The Sixteenth Century/ The Early Seventeenth Century. 8th ed. Ed. Stephen Greenblatt. New York: Norton, 2006. 1060-1.
Donne, John. "Holy Sonnets #1." The Norton Anthology of English Literature: The Sixteenth Century/ The Early Seventeenth Century. 8th ed. Ed. Stephen Greenblatt. New York: Norton, 2006. 1295.