This fable is about a mischievous wolf that decided to disguise himself as a sheep by wearing sheep skin or “sheep’s clothing.”
The disguise worked, and the farmer mistook the fox for a sheep, so much so that he slaughtered him.
This story with a moral lesson shows that if the mischievous wolf did not pretend to be someone or something, no that he is not, he would have not been killed by the farmer.