Is there a power that can sustain and cheer
The captive chieftain, by a tyrant's doom,
Forced to descend into his destined tomb--
A dungeon dark! where he must waste the year,
And lie cut off from all his heart holds dear;
What time his injured country is a stage
Whereon deliberate Valour and the rage
Of righteous Vengeance side by side appear,
Filling from morn to night the heroic scene
With deeds of hope and everlasting praise:--
Say can he think of this with mind serene
And silent fetters? Yes, if visions bright
Shine on his soul, reflected from the days
When he himself was tried in open light.

William Wordsworth

http://www.poemhunter.com/poem/is-there-a-power-that-can-sustain-and-cheer/