I just came back from a noontime Mass at St. Peter's in the Loop. Didn't especially notice how the people around me were dressed, but the question did come to mind as I walked home. Evidently, the curtain is about to go up on a performance of the musical hit "Wicked." A crowd was gathered around the front of the theater, and as I continued home, more and more people were passing by. I could tell they were going to see "Wicked" because they were in what used to be called their "Sunday best." It got me wondering when "Sunday best" quit being Church clothes and became theater clothes.
I'll bet if I had suggested to anyone in the "Wicked" crowd that they were overdressed, they would have given me all sorts of strange looks, while if I suggested to anyone in jeans and a t-shirt that they could dress for Mass the way they would dress for the theater, I may have gotten more than just looks.
Not that Jesus isn't happy to welcome those who wear jeans and a t-shirt to Church, of course. (He died for us, so he's willing to overlook these little things!)