I did not find that comment condescending, though I expected to when he mentioned that he was going to explain how the budget worked. In fact, the thing that struck me while reading the entirety of the piece was how well he advocated for his position and explained difficult ideas in an accessible way while not talking down to the nun or criticizing her for not sharing his point of view. If all scientists could write in such an effective way their politics would be much better received I'm sure.