This may sound like heresy, but I don't believe that anyone can be taught anything; the best we can do is find oppoortunities for them to learn, the 'teacher' role is one of finding and creating suitable learning opportunities for everyone and then facilitating their learning.
Anyway, what prompted this post was a recent reading of The Four Agreements (Don Miguel Ruiz). I have these on the wall in my 'office' (well that's what the taxman thinks my garden shed is!):
Be impeccable with your word - Speak with integrity. Say only what you mean. Avoid using the word to speak against yourself or to gossip about others. Use the power of your word in the direction of truth and love.
Don’t take anything personally - Nothing others do is because of you. What others say and do is a projection of their own reality, their own dream. When you are immune to the opinions and actions of others, you won’t be the victim of needless suffering.
Don’t make assumptions - Find the courage to ask questions and to express what you really want. Communicate with others as clearly as you can to avoid misunderstandings, sadness and drama. With just this one agreement, you can completely transform your life.
Always do your best - Your best is going to change from moment to moment; it will be different when you are healthy as opposed to sick. Under any circumstance, simply do your best, and you will avoid self-judgment, self-abuse and regret.
In these changing and challenging times, these seem especially appropriate...