Who, in spite of the jackdaw was trying to sleep,
At length, after trying and trying in vain
To stop the bird's talking, the sheep did complain.
"Do stop your noisy tongue! You very well know,
If I were a dog you would not treat me so!"
"Oh!" replied the jackdaw, "I know that is true,
But you forget that no dog is like you.
The reason I treat you so is very plain,
You're too big a coward to fight back again."
Source: Thummel: Aesop in Rhyme.