Giving his Shabbat Sermon, Rabbi Felderberg heard two teenage girls in the back giggling and disturbing people. So Rabbi Felderberg interrupted his sermon and announced sternly, "There are two of you here who have not heard a word I’ve said and I’m sorry but that is no way to treat the rabbi’s sermon." That quieted them down.
When the service was over, Rabbi Felderberg greeted people at the front door as usual. But a strange thing happened. About a third of the congregation approached him quietly and apologized for sleeping in shul during the rabbi’s sermon, promising it would never happen again.