The poem is about the art of poetry or what a poem should be. It is interesting to note that as MacLeish states what a poem should be, he illustrates it as well in the poem by successfully using paradoxes/contradictions and images to convey the idea that good poetry uses powerful images.
I can’t really say much about the speaker as a person because his voice sounds impersonal. For me the point of view that is used here is third person omniscient. He takes us from series of images that is not usual in our physical world. His voice brings us to those "entangled trees" and gets us closer to that moon climbing in the sky, just like the good poetry he speaks of. So we get why he's not supposed to sound all emotional and human.
This poem speaks to the readers and all who loves the art. It tells the readers to appreciate the poem as it is and do not give different meaning to it that will only speak for their own ideas. Poem should be felt. Readers should not look at it in its concrete meaning because poetry is an "art" and according to the dictionary, art is the expression or application of human creative skill and imagination, typically in a visual form such as painting or sculpture, producing works to be appreciated primarily for their beauty or emotional power. That is why we should not solved the poems like an equations, instead appreciate it on what it gives to us and let it be free.
The situation of this poem can be anywhere since the texts uses moon that can be seen in all places. And since the idea of this piece is that, the poem is timeless and motionless I can say that the poem has no definite setting. The poem also uses metaphors and irony. Lines 9-16 compare the "motionless" poem by implication to universality, the property of a literary work that makes it relevant for people of all ages and cultures. While line 12 compares night to an object that can be