In the PC(USA), we often like to refer to ministers as "Teaching Elders." In fact, this is technically the preferred language according to our denomination's constitution, but don't expect Presbyterians to stop using the word "minister" anytime soon. The point here is that we see "teaching" as one of the primary roles that a minister is to play within the life of a church.
That's not to say that "teaching" is the only role of the minister (the currently-preferred official language notwithstanding). In fact, although I appreciate the intention of the "Teaching Elder" language (to create a greater sense of parity with "Ruling Elders," laypersons who collectively do most of the actual governing within a local congregation), I can't help but feel that this language creates its own problems. Perhaps it's just the fact that I work in an educational institution, but my mind immediately conjures up an image of a professor giving a lecture. Too many people think of the sermon as a "lecture" as it is, especially in the Presbyterian church. We don't really need to reinforce that image! Ministers serve their congregations in a whole host of ways. Teaching is just one of the gifts that a good minister should have, and probably by no means the most important gift.
While it might be helpful to go into the multitude of roles of the minister in greater depth, that's a discussion for another time. For right now, I'm thinking about one particular role that came to my mind while listening to a devotional the other day: the role of minister as motivator. I don't particularly mean that a minister is a leader, although obviously a good leader should motivate those being led. Rather, I'm thinking of the quality of inspiration that a minister is in a position to offer people to do whatever work God is calling the person to do. Not necessarily by any "command" or specific request, but more in the way that people want to be better people when they see or hear godly people around them.
This kind of motivation might come in many forms. By engaging in acts of service, other people are motivated to serve. By offering kindness to people, others are inspired to be kind. By conveying profound insights of God's word in a sermon or a Bible study, listeners might desire to learn more on their own.
Of course, ministers also have the power to motivate in less positive ways. One hardly even needs to mention the ways that Christians have been led to do horrible things because some minister or another had preached some message of hatred or intolerance. As is often said in the Spider-Man comics and movies, "with great power comes great responsibility." Whether one calls them "Teaching Elders," or "pastors," or "priests," or whatever, ministers are ordained to a role of tremendous influence, and one they should always strive to take seriously.