Many years ago I attended a language course in bethel.
Everyone was dressed with suit and tie. Except me in my shorts and colourful t-shirt with don't know what slogan on it.
As they approached me if I could maybe change my outer appearance I said. "Dear brother so and so, I am very sorry, I thought it is just a language course with being able to think and learn in comfortable modest clothes. I am sorry but I just brought t-shirts with me for the whole 3 days."
I think the other brothers were jealous as they sweated the hell out of their close tied shirts during hot summer.