Why dost thou wound and break my heart,
As if we should for ever part?
Hast thou not heard an oath from me,
After a day, or two, or three,
I would come back and live with thee?
Take, if thou dost distrust that vow,
This second protestation now:--
Upon thy cheek that spangled tear,
Which sits as dew of roses there,
That tear shall scarce be dried before
I'll kiss the threshold of thy door;
Then weep not, Sweet, but thus much know,--
I'm half returned before I go.

Robert Herrick

http://www.poemhunter.com/poem/his-covenant-or-protestation-to-julia/