What has to be the moral in “the wolf in sheep’s clothing” ? ?

The moral of the story is that if you try to do harm to someone else you will end up being hurt in the end.

Explanation:

The Wolf in Sheep's Clothing is a fable about a wolf that pretended to be a sheep in order to try and get enough food. However, when he snuck into the sheep pen, the farmer decided to kill a sheep for food, and the sheep happened to be the same wolf trying to hide. The moral of the story is that if you try to do harm to someone else you will end up being hurt in the end.