As is probably well-known from my posts on this blog, I am Jewish, and the Jewish calendar is a lunar-solar calendar. This is why the Jewish holidays are at a different time every year (with respect to the Gregorian calendar) but still fall mostly within the same month window, due to leap months that happen on leap years. Unlike pure-lunar calendars, the Jewish calendar must be partially solar due to the fact that the three pilgrimage festivals (פסח, שבועות, סוכות) are all harvest times.
Because of that, life cycle events (such as בני-מצוה (bar/bat mizvah), נישואים (marriage), and יארצייט (yahrzeit = death… interestingly this is a Yiddish, not a Hebrew, word)) are commemorated in the synagogue by their Hebrew date, instead of their Gregorian date. Interestingly enough, that does NOT seem to hold for ימים-הולדת (birthdays).
There are a few reasons why I brought up this idea today. On June 14, which corresponded to ששה בתמוז (the sixth day of the Hebrew month Tammuz), I went on the Bike-To-Work Rally, and mentioned to some of the people at the Evanston Bike Club meet-up that it was my lunar birthday (indeed, 6 Tammuz in the Hebrew year 5747 corresponds to July 3, 1987). One of the other people mentioned that he was born on Washington’s birthday, Ash Wednesday, and his own birthday (the lattermost is obvious), which gives him several possible days to celebrate.
Then, this week that means that שבעה-עשר בתמוז (the fast of 17 Tammuz) was on Tuesday. Well, two years ago, that day corresponded to July 19, also a Tuesday. Though I didn’t write this following linked blog post for or on the 19th, it might as well have been. Because July 20 started the trip of a lifetime: תגלית (Birthright Israel)! For that reason, this week I will be daily changing my Facebook profile picture to a picture from the corresponding day of the trip. Today’s photo is a small sampling of the men of the trip in צפת (Safed/Tzfat).
AND… the תורה (Torah) reading from this week was פינחס (Phinehas), which corresponds to what I read on י”ט בתמוז, תש”ס (July 22, 2000, corresponding to 19 Tammuz, 5760) for my בר מצוה. There is definitely an intricate connection between the fact that I went to Israel on the same Hebrew date as when I became a בר מצוה.
In general, I just find it interesting that each calendar is constant with respect to itself, but non-constant with respect to other calendars.