On Mondays and Thursdays in the Old City of Jerusalem Jewish families celebrate the coming of age of their sons as part of the traditional Bar Mitzvah ceremony and parade through the Jewish Quarter of the Old City.
David Brent, in a blog post in the Times of Israel, described it this way,
“Every Shabbat, Monday and Thursday, Jews read from the Torah (the five books of Moses). Each week it is a different section. On Saturday, we read the whole section. On Mondays and Thursdays, we just read part of the section. When you read from the Torah, you have an opportunity to be called up for an honor. This honor forms the central part of the Bar Mitzvah ceremony. So basically, you can celebrate a Bar Mitzvah (or a Bat Mitzvah if you aren’t Orthodox) on a Saturday, Monday or Thursday. The problem with doing this on a Saturday is that you can’t take pictures. So in Israel, you end up having a lot of Bar Mitzvahs at the Western Wall on Mondays. Jews from all over the country (even from all over the world) come to this sacred place to observe this traditional ritual when a boy turns 13.”