| Quote #1
Close bosom-friend of the maturing sun; (line 2)
The word "maturing" reminds us that the sun is figuratively growing "older," its rays are getting weaker and the days become shorter.
| Quote #2
while thy hook (lines 17-18)
The hook is used for reaping but is also associated with death, i.e., the "grim reaper." But Keats softens the blow of this image by "sparing" the next patch of flowers, at least for now.
| Quote #3
Then in a wailful choir the small gnats mourn
The language of mortality is extremely subtle in this poem. The gnats are like a funeral choir, singing a requiem for the "dying" day. Also, the wind itself "lives or dies." The speaker has death on his mind in the final stanza.