The speaker of “Twelfth Song of Thunder” is a lover of nature. She’s a tree-hugger. Or maybe he’s a tree-hugger. We don’t get any identifying information here, so we’re just going to go with “she” in this case for the sake of balance. She, then, has a profound relationship with nature and its beauty. What’s more, she’s also a very observant speaker. She not only notices the big and spectacular phenomena of nature—like thunder—she also notices the small things, like a grasshopper chirping in the grass. She’s someone who has a strong conception of how all aspects of nature feed into one another, how the big voices connect with the small voices and vice versa.
Considering that “Twelfth Song of Thunder” is a chant, we can assume that this speaker also likes to sing. In this way, she also adds her voice to the “voices” of nature, in order to make one big happy harmony.