according to Leo Trepp.  During this time, the Jewish community defined the Bar Mitzvah as a son of the commandments.  But in the present day Jewish community, it is now defined as liable for the commandments.  These two meanings bear a huge significance in the Jewish culture.  The first definition along with the stage in life one is being initiated, serves as a welcoming into the congregation.  Prior to the Bar Mitzvah, a boy is circumsized and welcomed into the Jewish world.  But it is until the Bar Mitzvah that a boy can serve as witnesses for legal documents and be counted in a minyan [prayer service (Silberman 61)].  The second and more literal deifinitin of bar mitzvah (liable to the commandments) symbolizes a sense of maturity.  Before this blessed event,

A child is not required to keep any of the commandments which form the basis of Jewish life and thought.  Only as a matter of education is he asked to conform to the ways of his parents and community (B. Mitzvah 25). 

But when a boy reaches the age of thirteen, he no longer depends on his parents to tell him what is right and wrong.  He must now rely on his knowledge of the Torah (The Old Testament for Christians) and commandments to behave as how his community expects him to.