The name above this poem is John Donne's, but nothing here sounds like the seventeenth century. It is unrhymed free verse in plain modern speech, and I believe it is the work of the contemporary poet Louise Glück. Whoever wrote it, it is best read on its own terms. It is a quiet argument between two friends, one who believes in heaven and one who cannot, and it ends by finding what they share.
The opening is deliberately deflating. "I have a friend who still believes in heaven": that "still" carries a faint condescension, and the speaker immediately defends herself against it with "Not a stupid person." The comedy of "she literally talks to God" gives way to grudging admiration. The friend is "unusually competent," "brave too." The sentences are short and flat, like a list of evidence in a trial the speaker half expects to lose.
The caterpillar scene tests the two temperaments. The speaker is "moved by disaster" but "timid also, quick to shut my eyes," and her phrase "eager to oppose vitality" is strange and revealing, since she sides with the dying thing against the greedy, living ants. The friend watches and lets events "play out according to nature," yet she also intervenes "for my sake," brushing the ants from "the torn thing." Her courage includes tenderness. The friend turns this into an accusation: the speaker is the child with her head in the pillow, and the friend is the patient mother urging her to wake up.
The dream section reverses the poem's confidence. In waking life the friend is competent, but in the dream she is a figure of reproach, and the road has turned to winter. She promises that loving the world means hearing "celestial music," but when the speaker looks up she finds "nothing. / Only clouds, snow, a white business in the trees." The word "business" is wonderfully dry, a bit of ordinary speech that refuses to be awed. Then the image swerves into "brides leaping to a great height," beautiful and faintly alarming. The speaker's fear for her friend, "caught in a net deliberately cast over the earth," suggests that faith might be a trap. It also suggests the world itself is one, and that the friend is caught in it with everyone else.
Then comes "In reality," and the poem changes pace. The only sound is a birdcall that pierces the silence, so the music in this poem is earthly after all. The two women are "at ease with death, with solitude," and what divides them is how they explain that ease, not the ease itself. The friend draws a circle in the dirt around the motionless caterpillar. This is a small act of artistry, "something whole, something beautiful, an image / Capable of life apart from her." The language is the language of making art. The scene becomes a "composition / Fixed," and the lines grow shorter and calmer as the road darkens and the rocks glitter.
Structurally, the poem has no rhyme and no steady meter. Its long, prose-like lines sound like someone thinking aloud, and the dashes at the ends of stanzas leave each thought open. That looseness makes the final line land hard: "The love of form is a love of endings." It is the only truly aphoristic sentence in the poem, and it explains why the stillness is loved. A form is complete only when it stops, as a painting needs its frame and a poem needs its last line. The friend's heaven and the speaker's silence are two ways of loving that completion, one by promising it continues and one by accepting that it doesn't.
That is where the poem's significance lies. It does not let faith or doubt win. It lets two opposed minds sit side by side and agree on something deeper than belief: the beauty of things that are finished. It also quietly describes itself, since the poem too is a fixed composition that ends.