Traditionally, the father of a bar or bat mitzvah offers thanks to God that he is no longer punished for his child's sins.

[citation needed] The modern method of celebrating becoming a bar mitzvah did not exist in the time of the Hebrew Bible, Mishnah, or Talmud.

[20] Reaching the age of bar or bat mitzvah signifies becoming a full-fledged member of the Jewish community with the responsibilities that come with it.

These include moral responsibility for one's own actions; eligibility to be called to read from the Torah and lead or participate in a minyan; the right to possess personal property and to legally marry on one's own according to Jewish law; the duty to follow the 613 laws of the Torah and keep the halakha; and the capacity to testify as a witness in a beth din (rabbinical court) case.

[citation needed] According to Rabbi Mark Washofsky, "The Reform Movement in North America has struggled over the bar/bat mitzvah.

[23] The widespread practice is that shortly after a boy turns 13, they are called up for an aliyah,[24] the ceremony of reading a portion of the Torah section of the day.

[20][27] A bar mitzvah boy may learn to act as the ba'al korei, either for the entire service, for just his aliyah, or any range in-between.

[25] Any of these undertakings involves a steep learning curve and much practice, possibly taking a year of study, and is an impressive accomplishment.

In Orthodox synagogues, aliyot were and typically still are restricted to boys, with a girl potentially giving a d'var Torah at the end of the service.

Some Modern Orthodox girls give aliyot at women's services, with fewer than ten men (so as not to constitute a minyan).

[30] Bar and bat mitzvah parties among wealthy Jewish families in North America are often lavish affairs held at hotels and country clubs with hundreds of guests.

"[23] In May, 1992, the board of trustees of the Union of American Hebrew Congregations (now the Union for Reform Judaism), the synagogue arm of the Reform Movement, unanimously passed a resolution decrying "excesses of wasteful consumption...glitzy theme events, sophisticated entertainment...and expensive party favors", calling instead for "family cohesion, authentic friendship, acts of tzedakah (righteous giving), and parties suitable for children.

The majority of Orthodox and some Conservative Jews reject the idea that a woman can publicly read from the Torah or lead prayer services whenever there is a minyan (quorum of 10 males) available to do so.

In some Modern Orthodox circles, bat mitzvah girls will read from the Torah and lead prayer services in a women's tefillah.

Rabbi Moshe Feinstein, a prominent Orthodox posek, described the bat mitzvah celebration as "meaningless", and of no greater halakhic significance than a birthday party.

However, he reluctantly permitted it in homes, but not synagogues,[35][36] as the latter would be construed as imitating Reform and Conservative customs; in any case, they do not have the status of seudat mitzvah.

[39] There are documents that record an Italian rite for becoming bat mitzvah, known as an "entrance into the minyan" ceremony, in which boys of thirteen and girls of twelve recited a blessing, since the mid-19th century.

[41] However, it was the American rabbi Mordecai M. Kaplan held the first public celebration of a bat mitzvah as we understand it in modern times for his daughter on March 18, 1922, at the Society for the Advancement of Judaism, his synagogue in New York City.

[48] Instead of reading from the Torah, some Humanist Jews prefer a research paper on a topic in Jewish history to mark their coming of age.

[citation needed] Among some Jews, a man who has reached the age of 83 will celebrate a second bar mitzvah, under the logic that in the Hebrew Bible it says that a normal lifespan is 70 years, so that an 83-year-old can be considered 13 in a second lifetime.

The term has been in use since at least 1958, when Beverly Hills couple Janet and Sonny Salter held a bark mitzvah for their 13 year old dog, Windy.

As with charity and all other gifts, it has become common to give in multiples of 18, since the gematria, or numerical equivalent of the Hebrew word for "life", ("chai"), is the number 18.