Drayton's sonnet begins on the defensive. The speaker imagines sceptics, "misbelieving and profane in love," who hear him call his beloved a worker of miracles and conclude that he is flattering her to show off, writing "my skill in verse to prove." The rest of the poem is his reply. He will answer the accusation with evidence and call his witnesses like a lawyer.
The first piece of evidence is the poem itself. His Muse was "dumb-born" and his hand a "cripple," "lame by kind," meaning lame by nature. Now the one speaks and the other writes, "One by thy name, the other touching thee." The syntax is knotty, and the line is a little awkward as a result. The logic is clear, though: his ability to write at all is the first marvel, and the beloved is both its subject and its cause. There is a neat irony here. He is accused of using verse to show off, and he defends himself with a sonnet that is quite showy. I suspect Drayton knows this and enjoys it.
From line 9 the poem borrows the language of the Gospel healings. Blind eyes are opened ("Blind were mine eyes, till they were seen of thine"), deaf ears are cured, the dead are raised (hopes "which long in grave had lien"), and demons are driven out ("foul spirits, cast out in me"). The order matters. The list begins with the senses, which are physical and visible, and moves inward to vices, hopes and finally "unclean thoughts." The deeper the miracle, the harder it is for any outsider to check, so the speaker's case rests on the one witness who cannot be cross-examined, himself.
The grammar backs up his defence. Nearly every verb in the sestet is passive: eyes "were seen," ears "healed be," vices "cur'd," hopes "reviv'd," spirits "cast out." The speaker is never the agent. A flatterer is active, calculating and working on his audience. This speaker presents himself as a patient on whom something has been done, and the whole sentence structure insists on it.
The sound pattern does similar work. The rhyme scheme, roughly ABBA BCCB DBBD BB, fits neither the Petrarchan nor the Shakespearean model. Instead the long *-ee* sound takes over: nine of the fourteen lines end in "thee," "me," "see" or "be." "Thee" alone closes four lines (2, 8, 11 and 14), so the beloved keeps returning at the line-ends, and "me" and "thee" are rhymed together in the final couplet. Whether this is deliberate design or the strain of finding so many rhymes, the effect is insistence, like a witness repeating the same testimony. Line 14, "Only by virtue that proceeds from thee," nearly restates line 11, "virtues sprung from thee." "Virtue" here can mean moral goodness, but in older English it could also mean power or healing force, so the word suits a poem about cures.
The word "see" ties the poem together. In line 5 it is a challenge to the doubters, who are named a second time as "unbelieving" and commanded to "see miracles" for themselves. By line 9 seeing has become the miracle itself, as the speaker's blind eyes are "seen of" his beloved's. Evidence and cure are described with the same word.
Behind all this is the old habit of love poetry of treating the beloved as a saint. Drayton pushes it almost to the edge, since she heals, resurrects and exorcises. There is a tension he never quite resolves. The sceptics are called "profane," yet it could be argued that the more profane act is lending sacred miracles to a human lover. The sonnet claims the high ground and borrows the Gospel's vocabulary without apology.
What makes it worth reading is that it is love poetry arguing about love poetry. It anticipates the reader's doubt, gives that doubt a place inside the poem, and then tries to win it over. By the final line the question is whether we remain among the "unbelieving" or whether the accumulating miracles have persuaded us, which is exactly the choice the speaker has set for his critics.