Re: so should we stand for the homily?
Actually, since standing was the gesture when listening to a teacher or philosopher, there are quite a few times when guys like St. Augustine or St. John Chrysostom were recorded as telling new Christians to feel free to sit down during their homilies, because it was going to take a while. It seems to have always been usual for people to sit down for the homily; or to briefly continue standing from the Gospel, and then sit.
But this also happened sometimes in the ancient world, if a philosopher or teacher or another speaker was addressing a large crowd in a secular way, but there wasn’t a tall place for him to stand and address the crowd; or if the crowd was not sitting in amphitheater seats and able to look down on him from all directions. Sitting down on the ground to hear a speaker allowed everyone to hear and see more easily, and reduced problems with shoving, pickpocketing, etc.
I like studying the Fathers when I find out little facts like this, that make sense and also explain a lot of normal things we do.