Old Testament -- Get Circumcised.

New Testament -- Be of Circumcised heart.

In Jewish tradition, male infants are typically circumcised shortly after birth in a ceremony called a "Brit Milah" (or "Bris"). This ritual is performed on the eighth day of life, unless there are health concerns. The Brit Milah symbolizes the covenant between God and the Jewish people, as established with Abraham in the Torah.

By the time a boy reaches his Bar Mitzvah at age 13, he has usually already been circumcised as part of this earlier ceremony. Therefore, circumcision is not a part of the Bar Mitzvah itself; rather, it is a separate ritual that occurs in infancy. The Bar Mitzvah focuses on the boy's coming of age and his responsibilities within the Jewish faith.