Classic Poem

How often, these hours, have I heard the monotonous crool of a dove —
Voice, low, insistent, obscure, since its nest it has hid in a grove —
Flowers of the linden wherethrough the hosts of the honeybees rove.

And I have been busily idle: no problems; nothing to prove;
No urgent foreboding; but only life's shallow habitual groove:
Then why, if I pause to listen, should the languageless note of a dove
So dark with disquietude seem? And what is it sorrowing of?