This poem pulls together a lot of threads, in terms of tone. It's like our speaker has pulled us aside to confide her personal philosophy on life and death. We can tell she's serious, but the way she's talking also carries a sense of energy and vibrancy. Even when she's describing death, the creative and vivid descriptions tell us that the poem is not going to be all somber and fearful. And while, on the one hand, all the repetitions she uses can make the poem almost sound like a chant, our speaker also manages to sound calm and reasonable. She uses logical words like "Therefore." She'll build up the momentum with those long sentences, but then slow things down to tell us something plainly.
The music of her language works throughout to enrich and reinforce what she's telling us. We'll give you a few examples. At the beginning, the hard, abrupt sounds of "snaps," "shut," and "pox" make us jump a little in fear (lines 4 and 6). Then, in line 9, the language becomes more open and expansive with all those vowel sounds in "through," "door," "curiosity," and "wondering." That shift in language meshes with our speaker's declaration that she wants to step out from under fear, and be open to the possibilities that might exist in death. And try reading this line aloud: "each name a comfortable music in the mouth." It takes a bit of effort to make all those m-sounds, doesn't it? We can't do it without feeling extra aware of all that music that's going on in our mouths.