Bar and Bat Mitzvah to the event. However, this does not delay the onset of rights and responsibilities of being a Jewish adult which comes about strictly by virtue of age. The obligation to lay tefillin begins when a boy reaches bar mitzvah age. The common custom is for the bar mitzvah boy to begin putting on tefillin one to three months before his bar mitzvah. This way, by the time he is obligated in the commandment, he will already know how to fulfill it properly. The first mention of a party associated with a synagogue bar mitzvah was in the 13th century, so
Milkhemet Mitzvah yet plowed their field before the war. All of these exemptions are given only in the case of "Milhemet Reshut." Talmud Scholars of both the Jerusalem and Babylonian Talmuds discussed the nature of the wars commenced by the Israelites during the biblical era (Tanakh) generally tend to describe the conquest of the Land of Israel in the Book of Joshua as Mitzvah Wars, while the wars fought by King David were meant to expand his kingdom, hence regarded as discretionary wars. Modern scholars also suggested that Mitzvah Wars originally signified a religious act. Questions about the halakhic justification for war