Thus, you can see that what matters more than anything else in a teacher is the way in which he regards his holy calling. That is not without significance, for the most Important things In teaching and in education are those which are imponderable. A teacher who enters his classroom with this feeling in his heart achieves something different from another. Just as, even in everyday life, it is not always the largest thing physically that determines our standard but something quite small, so also it is not always what we do with the largest number of words which carries most weight, but sometimes it is that perception, that feeling which we have built up in our hearts before we enter the classroom.
There is one thing especially which is of great importance. That is that we must quickly strip off our narrower, personal self like a snake skin when we go into the class. A teacher may in certain circumstances, because he, as is sometimes said with such self-satisfaction, is also only human, go through all sorts of experiences between the end of a class one day and beginning again on the next. It may be that he has been warned by his creditors, or he may have had a quarrel with his wife, as does happen in life.
These are things which bring disharmonies. Disharmonies of this kind give a man’s frame of mind a certain tendency; so also do happy joyous feelings. The father of one of your pupils, if he particularly likes you, may have sent you a hare after he has been out hunting, or a bunch of flowers perhaps, if you are a lady teacher. What I mean is that it is quite a natural thing in life to have moods of this kind. As teachers we must train ourselves to lay aside these moods and to give ourselves up entirely to the content of the subject we are going to teach, so that we are really able in presenting one subject to speak tragically, taking our mood from our subject and then to pass over into a humorous mood as we proceed with our lesson, in this way entering completely into our subject.
https://rudolfsteinerquotes.wordpress.com/2021/03/13/laying-aside-moods/