I think it is a VERY serious thing to step into the ministry because not only do you have to give an account for those you minister over and how you ministered - you could destroy people with your ministry if it isn't kept in check. Destroy them for eternity! Does anyone not think of that when they attend a Seminary or become a preacher? I've seen several count it as nothing, like it was just something to do to get recognition for being something "great" in God - then they go out and destroy other people with their wacky jack doctrines.
James 3:1
My brethren, be not many masters, knowing that we shall receive the greater condemnation.
We have had people tell us that we were supposed to be in the ministry, but I wonder why didn't God tell us that? Simply put - you can't follow other people's will for your life or what they "think" God wants you to do. Doing so will only result in destruction of yourself and possibly others - I've seen it happen!! We had friends who did what everyone else was doing and they are back in sin, broken and destroyed. They are the shining beacons of the choices that we don't want to make so hastily.
So the next time you feel that you are wondering what God wants you to do, just live in His will for this present time. Don't jump ahead of God in haste and don't sit still when He says GO! Live in God's will for right now.
Clark's Commentary on James 3:1 says it well:
This caution is still necessary; there are multitudes, whom God has never called, and never can call, because he has never qualified them for the work, who earnestly wish to get into the priest’s office. - Their case is awful; they shall receive greater condemnation than common sinners; they have not only sinned in thrusting themselves into that office to which God has never called them, but through their insufficiency the flocks over whom they have assumed the mastery perish for lack of knowledge, and their blood will God require at the watchman’s hand.