In the place where I used to work, there used to be a person suffering from some mental troubles whose daily activity was to insult passers by and whose favorite place was not far from the pharmacy!
One day he knocked the pharmacy doors searching for a solution to his skin problem. I treated him like any other patient, listened to his complaint, advised him and gave him the needed remedy.
The result of such a normal act was astonishing: Never after that day did he insult anyone before me, when it is out of control, he just leaves his favorite place. More than this, he came back again for a health problem and I noticed he was using some polite expressions, such as “Thank you!”.
He was doing his best to respect me, just the way I showed respect to his person.