On a few occasions, I was able to speak with him outside of class. He gave a series of lectures at a local church. I attended a few of those and was able to talk to him briefly about those. I visited him in office hours once to ask for a clarification on a point in his lecture. He gave a full and complete clarification and seemed to have no problem giving me the time to do that. A classmate of mine has had him for multiple classes and she attests to his approachability. Even in class (lecture hall of ~250 students at least), he made you feel very able to ask him questions.