I would have gone; God bade me stay:
I would have worked; God bade me rest.
He broke my will from day to day,
He read my yearnings unexpressed
And said them nay.

Now I would stay; God bids me go:
Now I would rest; God bids me work.
He breaks my heart tossed to and fro,
My soul is wrung with doubts that lurk
And vex it so.

I go, Lord, where Thou sendest me;
Day after day I plod and moil:
But, Christ my God, when will it be
That I may let alone my toil
And rest with Thee?

Christina Georgina Rossetti

http://www.poemhunter.com/poem/weary-in-well-doing/