Question

What is the moral for this story? Why the lion thanked the mouse? Why do the lion roars?

Answer 1

Answer:

The moral of the story is that mercy brings its reward and that there is no being so small that it cannot help a greater. Later English versions reinforce this by having the mouse promise to return the lion's favor, to its sceptical amusement.

Lion roars because it was his character a person can not leave his character.