When I first began teaching publicly, as a youth minister in the early seventies, I taught in a conversational, dialogue style. After all, there were just twenty-five kids. When my material wasn't all that useful, one of the students would raise a hand and say, "Can we move on?" Then I'd realize I was missing the mark, or I had overstayed my welcome in the Book of Leviticus, and we would move on.

I stayed with that style for more than a year, but then we started outreach programs, and all of a sudden the group jumped from 25 to 150. My teaching style soon became inappropriate for the larger group; I actually had to start putting together formal messages. In a panic, I went to a senior pastor friend and said, "I have to start giving full-blown messages to 150 high school students. What do you suggest?"

He said, "Well, if I were you, I would get a copy of Berkhof's Manual of Christian Doctrine and just start at chapter 1 and teach these kids." Sounded fine to me. So I read the first chapter ...