You shouldn't date him, not because of his age, but because he became jealous over something he had no right to be jealous about. Imagine how jealous he would be if you were dating, You need to walk away and stay away from him.
As for the age thing. When i was that age I didn't know any 19 years old that were mature enough for me to date. Plus since I spent time in drinking establishments with my friends, a 19 year old wouldn't be allowed to join me, that is going to cause tension.
