This poem takes us on a stroll through the countryside in spring. It's a natural setting, but not a completely wild place. We get the sense there are farms around, and pastures. We walk through weeds in a field, and pass by a grove of trees. There are lambs frolicking on a hillside. The sky is baby blue and reaches right down, connecting heaven and earth Everything is bright and blooming and bursting forth. This is the Garden of Eden, or very close to it. Man lives at peace and with joy in the vibrant natural world.
Towards the end of the poem, though we don't leave the scene or the season, there's a definite cloud that passes overhead. There's a hint behind it all of how this scene of spring is or will be lost. We step back from the beauty a little bit – did you notice no more description of nature appears in the last six lines? We flash back for a second to the original Eden, with Adam and Eve. But mostly we feel distant from it, faced with the knowledge of man's expulsion from Eden, and the change of seasons to fall and winter. Likewise, we have a glimpse, like a memory, of a young girl and boy looking all cute and innocent, maybe frolicking with the lambs. But we can't seem to focus on them anymore, since we're caught up in asking God to keep them from sin.