I think he is just telling them to chill. He knows that they are just little kids so he’s like you guys just need to be normal and you are going too fast. He’s just saying you should just relax and happy with each other, and don’t be so extreme. I think that romeo and Juliet are just little, so they probably won’t take his advice, but it is good advice. They both seem like really extra people, because they barely know each other and they are already getting married, so they probably will just be like whatever old man.