I’ve learned a few things after over a decade of public speaking and 25 years of teaching in college classrooms. The one thing I know now is that you can never really know what people are thinking. Sometimes, I think I’ve done a horrible job, and an audience seems bored and unimpressed. Later, I find out they were deeply challenged and quiet because of contemplation and conviction. I interpreted their demeanor all wrong! Or, a class that felt disconnected and sullen later sends emails saying it was the “best class they’ve ever had.” Or sometimes an audience cheers and celebrates, but I wonder if the message will bear any lasting fruit. I cannot see God’s invisible work in the soul. I’ve learned, therefore, to minimally evaluate a class or public presentation and leave the results to God. One can’t always measure impact or effectiveness, so it’s best to move on, not worry about it any more, and thank God for the blessing of serving others.