Perhaps To Vittoria Colonna.
S' alcun legato è pur.
He who is bound by some great benefit,
As to be raised from death to life again,
How shall he recompense that gift, or gain
Freedom from servitude so infinite?
Yet if 'twere possible to pay the debt,
He'd lose that kindness which we entertain
For those who serve us well; since it is plain
That kindness needs some boon to quicken it.
Wherefore, O lady, to maintain thy grace,
So far above my fortune, what I bring
Is rather thanklessness than courtesy:
For if both met as equals face to face,
She whom I love could not be called my king;--
There is no lordship in equality.