Ok ladies, I need a bit of advice.

My fiancé and I recently talked to his parents about us being engaged and our plans for the future. His mother has been wonderful, and while she seems as though she may not agree, she has been supportive and happy for us. His dad is extremely stubborn and is a very dominant personality. He has high expectations, one of which is that we will listen to his advice and do exactly what he says. The issue here is that his dad is being rude and condescending. My fiancé had some issues with his ex and was estranged from his family for a while because of his devotion to her (she treated him very badly and they would not support his moving to be with her) so I understand his parents not being as sure about us, but this is getting to a boiling point. His dad wants us to go to dinner with him so he can talk to us, but we both know that this is going to be him basically saying we don't know what it takes to be married and we shouldn't do it. Obviously marriage is very difficult, and we know that it is going to take work, but we both feel ready to take this step. It is weighing really heavily on my fiancé, and I'm trying to help, but I don't know how to approach the situation with either him or his dad.