An expert is someone who tells you why you can't do something, a teacher is someone who shows you how you can.
An expert sells, a teacher gives.
An expert seeks authority, a teacher seeks accomplishment.
An expert demands respect a teacher earns respect.
An expert is someone you have to return to when things go wrong.
A teacher is someone who has prepared you to repair it yourself.
An experts reward is silver and gold. A teachers reward is teaching itself.