One of the most important human figures in Judaism is Moses, and indeed there's good reason for this. He spoke to God "face to face", something that no other prophet could claim until Christ Himself arrived (Deuteronomy 34:10). One interesting thing God said about Moses is that he was "as God" to both Aaron (Exodus 4:16) and even to Pharaoh.
This is no small thing. God, as we know, is very zealous for His glory. He doesn't share (Isaiah 42:8). Therefore, to tell Moses "you shall be as God", and even to call Aaron His prophet, is really quite profound. What does it mean?
We actually see the answer in the very same verse. It is a matter of authority. As God commands, and requires obedience, so also did Moses' commands carry authority. Pharaoh was sinning when he disobeyed Moses, whereas Aaron, far from speaking on his own authority, was speaking on behalf of Moses.
But just as Aaron spoke what Moses commanded him, Moses spoke whatever God spoke to him. Moses was not permitted to deviate from God's word. It is interesting to note, then, that there is actually one recorded instance in which Moses did deviate from God's word. In Numbers 20, Moses was commanded to speak to a rock in order to bring forth water for the ever-grumpy Israelites. But Moses decided to take the glory for himself, and so rather than speaking to the rock, Moses said "Hear now, you rebels! Must we bring water for you out of this rock?" and gave it a jolly good smack with his staff. The result? A very angry God prevented him from taking the Israelites into the promised land, instead stopping him just shy, ending his life on a mountain overlooking the promised land.
This has some very serious implications for authority figures in the Church. If Moses, who was literally told "I have made you as God", can be punished for deviating from God's word, what fate is in store for those people? A teacher who deviates, as did Moses, will be judged far more harshly than the dude sitting behind you in the pews. And woe betide the false prophets! Those who form or lead false religions, woe to them. Even a true prophet has no authority beyond that which God has given him, and so those to whom such authority was not granted will surely be condemned.
I can't imagine I have a large following of teachers, be they legitimate authorities in a Biblically based church, or false teachers in a heretical church. Nevertheless, on the off chance I do reach such authorities, let Moses' example be a warning, for as James says, teachers shall receive stricter judgements (James 3:1).
To those of you who are not teachers, there is still much you can learn here. Specifically, test your teachers. No one is God but God alone, and even the best of teachers are still fallible men. We sin, we make mistakes, we even bow to pressure. Not to mention, again, false prophets do exist, and they do make claims about their authority. The only effective defence is an adequate study of scripture (2 Timothy 2:15), and a true teacher will always submit to such tests (Acts 17:10-11).