I'm loathe to slink way from this thread with the feeling that there is "nothing I can do", even if I know I'm not called to be a teacher. God used Ray Smith and B-T on me.
Ray calls himself a teacher--and IS a teacher. He defines it very simply without any psuedo-spiritual mumbo jumbo. A teacher is somebody from whom people learn. Ray 'taught', I learned, and continue to. He is 'my teacher'.
If that definition is the case, then there are teachers of Truth, there are false teachers, and there are non-teachers (those who may attempt to teach but are unable or not blessed with 'results' which disqualifies them from the legitimate 'title'; or those who may not attempt to teach at all). The standards for a teacher of Truth are quite high and anyone who follows that leading is held to those higher standards. The scriptural admonition is to let there not be too many teachers. Yet some are called...not too many.
It seems to me the major warning Ray is giving is that we know what to expect when we try to 'convert' our former pastors, or family and friends, or spouses and children. It's an evil thing to be rejected--an evil that the Lord Jesus endured infinitely greater than any of us. It's an experience of evil given to us whereby to humble us, like all evil experiences are. We may be full of zeal, but not wisdom (like Peter in the Garden with the sword). We may be full of ourselves in many ways that "failures" cure us of.
We can't 'preach' a Gospel of a Sovereign, loving God who calls many and chooses few if we're not speaking out of Love and accepting His will.
Few should be teachers. I've known that since forever was new. A week or two on facebook was a humbling reminder. Some don't have it very right, and others have nothing to 'teach' at all. But that doesn't mean we can't do something to be part of the 'sent' so that preaching, hearing, and believing can happen according to the Will of God, just as it did/does for us.