What is so great about this poet is that she can really turn a compact phrase. I have heard Emily Dickinson sneeringly called, "the undergraduate's favorite poet" and at the same time critical giants like Harold Bloom consider her one of the greatest. Whether you think her poems are clever (in the worst sense of the word) or clever (in the best sense), the first four lines of this particular poem illustrate poetic thinking at its best.
What is so great about this poem, and especially the opening, is that it is wound tight with creative energy. The meaning is fairly straightforward, but the resonance it leaves with us in just a few words is impactful. Most of the impact comes from one of the most fundamental functions poetry satisfies psychologically: to simultaneously convince us that we understand what is going on and at the same time leave some part of us feeling that we do not completely understand. In this case, the effect is rendered mostly through playing on the difference between light and heavy words.
To illustrate this point, consider the effect if the fourth line ended with "cathedral songs" instead of tunes. It's a more boring poem. More literal. Even (perhaps especially) if we reworked it to rhyme. Why? Because the stroke of genius in the use of "tunes" is that at least one of its meaning is as a light word--meaning something between a song and a jingle. This is somewhat out of place--if we really thought about it--in a cathedral. But we do not stop to think about it. Because, besides being aided by the natural sense of "rightness" a rhyme creates, the poem has also set up a precedent for the use of words with possible "light" valences in an otherwise heavy situation.
Consider the following dissection:
The "light" words are slightly outnumbered and out of place. But only slightly--because they hold enough literal sense in the context of the grammar and syntax of the poem as to be passable in furthering that literal meaning. More than passable, they are interesting, because their ulterior meanings make them slightly strange.
The entire poem, in fact, is a remarkable example (as is much of Dickinson's work) of the importance of strangeness to poetry. Good poems often say what they mean while lightly scattering ulterior motives and messages throughout the poem. Or if not messages, at least unusual or interesting relationships.
Every word has many charges to it, and so, besides sending our mind in the main direction, we find our minds rapidly stimulated by the cumulative effect of these additional meanings. The overall effect is a sense of delight, or scope, or fascination with a poem. And the best ones, read over and over, have the same electrochemical effect upon us every time.
Perhaps a little more about that next Monday.