I tried to vounteer to teach Sunday School at my aunt's church (when I thought I might want to go there, before realising they were, well, not-very-Biblical). The pastor said, "You have to be trained!" I asked in what. He said, "In teaching." So, five years of university and two degrees were not enough? I said, "Um, I'm a teacher." Him, "But you have to know about the Bible!" I said, "I majored in Biblical Studies at university." (And got the highest mark that year for the bible knowledge test - a 90%, 20% higher than the next-highest mark!) He said, "We'll see."
I got the message.