What lesson give us of the tell tale heart? give me two reason

The Tell-Tale Heart is a short story by Edgar Allan Poe, first published in 1843. IN the story, an unknown narrator tells how he followed and finally killed an old man because he  was afraid of his blue eye. After the murder, the narrator tried to hide the body from the police. The lesson is a moral one: the danger and power of a guilty conscience. When the police comes to his house, he seems to be calm. However, he starts listening to the beating of a heart which makes him start feeling nervous. It gets to a point he cannot bear it anymore, so he confesses the crime to the police. At this point we can say that another moral can be that one should try to confront fears somehow and also be conscious about the actions we take.

The guilty soul of the narrator in the story was like a haunting ghost in his mind who made him first listen to the corpe´s heart and finally confess.