Wonder in happy eyes 
Fades, fades away: 
And the angel-coloured skies 
Whisper farewell. 
 
Loveliness over the strings of the heart may stray 
In fugitive melodies; 
But Oh, the hand of the Master must not stay, 
Even for a breath; 
 
For to prolong one joy, or even to dwell 
On one rich chord of pain, 
Beyond the pulse of the song, would untune heaven 
And drown the stars in death. 
 
So youth with its love-note dies; 
And beauty fades in the air, 
To make the master-symphony immortal, 
And find new life and deeper wonder there.
Alfred Noyes
http://www.poemhunter.com/poem/the-symphony-3/