Analysis of Sonnet to the Nightingale

O nightingale that on yon blooming spray
Warblest at eve, when all the woods are still,
Thou with fresh hopes the Lover’s heart dost fill,
While the jolly Hours lead on propitious May.
Thy liquid notes that close the eye of Day,
First heard before the shallow cuckoo’s bill,
Portend success in love. O if Jove’s will
Have linked that amorous power to thy soft lay,
Now timely sing, ere the rude bird of hate
Foretell my hopeless doom, in some grove nigh;
As thou from year to year hast sung too late
For my relief, yet had’st no reason why.
Whether the Muse or Love call thee his mate,
Both them I serve, and of their train am I.