Of two fair virgins, modest, though admired,
Heaven made us happy; and now, wretched sires,
Heaven for a nobler doom their worth desires,
And gazing upon either, both required.
Mine, while the torch of Hymen newly fired
Becomes extinguish'd, soon - too soon - expires:
But thine, within the closing grate retired,
Eternal captive, to her God aspires.
But thou at least from out the jealous door,
Which shuts between your never - meeting eyes,
May'st hear her sweet and pious voice once more:
I to the marble, where my daughter lies,
Rush, - the swoln flood of bitterness I pour,
And knock, and knock, and knock but none replies.
George Gordon Byron
http://www.poemhunter.com/poem/on-a-nun/