Lama Ole’s answer:
You should realize that aggressive people are actually in a weak position. A man who is doing well doesn’t have to bother anybody because he has enough power and security within himself.
So, in your case, the man has a problem and it is not your problem. Maybe you stepped on his tie in some previous life, but for you that is over. Now you’re standing in front of a person who is disturbed. There you are the doctor and have to decide how to treat him. He has come to you with his problem, and now you must decide how you want to help him.
There are various possibilities, but one thing must not happen: you must not get angry. If you get angry, you are on the same level as he is. Then you are also weak and will make mistakes.
Instead, you can talk with him directly and say, “Hey, listen, do you have a problem? Can I help you somehow?” Probably the best way to get rid of him is to be overly friendly and psychologically helpful: “You have this problem. I’ve heard all about it. How can we help you with it?” You talk about his problems until he has enough of you and finds someone else he can bother. If you say, “I talked with my Lama about your problem,” then you will be rid of him right away.