"When I do good, I feel good. When I do bad, I feel bad." Abraham Lincoln 

This statement is trying to say that when you do something right you feel good about it. When you do bad you feel bad inside. When you do good you feel proud of yourself. When you do something bad you feel guilty and bad. When doing bad you feel bad inside like if you steal from someone you feel bad afterwards inside because the guilt. When you do good you feel proud of yourself and are happy and feel good. An example of doing good and feeling good is opening the door for a person.