What can I give thee back, O liberal
And princely giver, who hast brought the gold
And purple of thine heart, unstained, untold,
And laid them on the outside of the wall
For such as I to take or leave withal,
In unexpected largesse? am I cold,
Ungrateful, that for these most manifold
High gifts, I render nothing back at all?
Not so; not cold,--but very poor instead.
Ask God who knows. For frequent tears have run
The colours from my life, and left so dead
And pale a stuff, it were not fitly done
To give the same as pillow to thy head.
Go farther! let it serve to trample on.

Elizabeth Barrett Browning

http://www.poemhunter.com/poem/sonnet-viii-what-can-i-give-thee-back/