"There's hardly anything sadder than to run into a teacher of the Bible who does not believe the Bible and may even have a guilty conscience about making a living from teaching the Bible. I have known a few such folk, and they, perhaps above all Bible teachers, need our prayers. It is true, of course, that God can write straight with a crooked stick. We all know the story of God's using not only Balaam, but Balaam's donkey to convey the truth. But these examples are far from ideal. Jesus wanted disciples, not mere marionettes that he could manipulate to talk for him.
"The warning that "not many of you (Christians) should presume to be teachers" could be further amplified if we are talking about people who are not even inclined to believe the Bible, or even worse are prepared to caricature, ridicule, and stereotype the Bible, or use it to pursue their own unbiblical agendas. We don't need Bible teachers like that, especially in a biblically illiterate culture already prone to dismiss the Bible as a relic of the past."
Ben Witherington III, Is There a Doctor in the House? An Insider's Story and Advice on Becoming a Biblical Scholar (Grand Rapids: Zondervan, 2011), 126.