Smoke
I felt inclined to repost this poem, an old favourite from George MacDonald that I can recite from having written it so many places many years ago.

Picture from here.
Smoke
Lord, I have laid my heart upon thy altar
But cannot get the wood to burn;
It hardly flares ere it begins to falter
And to the dark return.
Old sap, or night-fallen dew, makes damp the fuel;
In vain my breath would flame provoke;
Yet see — at every poor attempt's renewal
To thee ascends the smoke!
'Tis all I have — smoke, failure, foiled endeavour,
Coldness and doubt and palsied lack:
Such as I have I send thee! — perfect Giver,
Send thou thy lightning back.
George MacDonald