Do you know the difference between teaching and preaching? Preaching is helping people to understand the Bible and think of application for themselves. Teaching is looking for learning to happen, not just reciting what's been read. But Christians today have a hard time articulating faith beyond an emotional level.
Humans so often and easily forget God, that God continually uses leaders, prophets, and judges to remind us of who God is. Teaching can help people not only know about God but to know God. After all, who Jesus is and what He does is why we have the Bible and why we must teach it.