Teachers who are not perfectly calm, who do not have an endurance that never fails, and a quietude which nothing can disturb, who have no self-respect — those who are like that will get nowhere. One must be a saint and a hero to be a good teacher. *One must be a great yogi to be a good teacher. One must have a perfect attitude to be able to exact a perfect attitude from the students. You cannot ask anyone to do what you don't do yourself. That is a rule. So look at the difference between what is and what ought to be, and you will be able to estimate the extent of your failure in class.*