In what types of cases can one not build an opening (window or door) from his house? In extending an existing door, there are issues regarding not only seeing into the neighbor’s property but also in doing so, one gains rights to more space of the commonly shared courtyard as the space directly in front of the door belongs to the owner of the house. What if one has something that juts out into public space? There are two stories brought of people who came before rabbis who ruled they had to get rid of it but the rabbis themselves had something similar or the same in their own property. The stories highlight the needs of leaders to hold themselves to higher standards or at least to the same standards as they demand of others. In the context of things one must do to remember the destruction, the gemara discusses the concept of moderation and the concept of not demanding something of the people that they will not be able to keep.