What is a bamitsfar?

Answer 1

Do you mean Bar Mitzvah? If so, this the coming of age of Jewish male children (Bat Mitzvah is the same thing for female Jewish children). It is at this age that the children become responsible for adhering to Jewish laws and tenets of their faith (nb. it is the children who are referred to as Bar/Bat Mitzvah - not the ceremony of them attending their first sabbath service).