In honor and recognition of which, should you choose to observe the day, you should refrain from food and drink from sunrise to sunset (or, if you prefer, from Daybreak to Sundown). And indeed the 10th of Tevet, say some, should always be observed on, well, the 10th day of Tevet, because a phrase in Ezekiel suggests that this really is the exact day that the events it commemorates occurred. That means if the holiday falls on Shabbat, as it will in December 2013, then you observe it then; the only other fast day of which this is true is Yom Kippur. (As with all fasts, the ill, the elderly, the infirm, or the pregnant or nursing are exempt from fasting requirements.)

In recent years, many have looked upon the 10th of Tevet and its message of sorrow and utilized it as a day to remember the victims of the Holocaust. Indeed, since Yom HaShoah comes in Nisan, during which mourning is supposed to be prohibited, observant Jews tend to prefer today for remembering the 6 million.

Tenth of Tevet [Wikipedia]
10 Tevet [Chabad]

If we Jews, never a well-liked bunch, were to mark each and every injustice that had befallen our people over time, we would spend most of our days commemorating catastrophes.

Conveniently, then, there’s the Seventeenth of Tammuz, a catchall day during which, according to tradition, some of the most gruesome chapters in Jewish history unfolded. It began with Moses, strolling down the mountain after conferring with God and seeing that his impatient people had meanwhile found other, more glittering idols to worship. Furious, Moses smashed the tablets, the first of many no-good things to happen on the Seventeenth of Tammuz. The Babylonians crashing the gates of Jerusalem in 586 B.C.E.? The Romans burning the Torah in 50 C.E.? The Libyans confiscating Jewish property in 1970? It’s all here, on one grim day.

The Seventeenth of Tammuz also marks the beginning of a period known as the Three Weeks, or Bein Ha’Meitzarim (“between the straits”), which ends with Tisha B’Av. It’s a period of general mourning in which weddings and celebrations are forbidden and life takes on a generally somber tone.

Together with three other occasions on the Jewish calendar—the Third of Tishrei, the Tenth of Tevet, and the Thirteenth of Adar—the Seventeenth of Tammuz is more of a historical reminder than a religious ritual. This is why the fast is faster and the restrictions not so strict.

ANY BAD GUYS?

Nothing but: Nebuchadnezzar the Babylonian, besieger of Jerusalem and destroyer of the First Temple; Pope Gregory IX, confiscator of all known copies of the Talmud in 1239; even King Menashe, a malicious Biblical Jewish monarch who, on this date, placed an idol in the Holy Sanctuary of the Temple.

WHAT DO WE EAT?

This being a day of fast, not much. But take heart: fasting on the Seventeenth of Tammuz begins at dawn and ends with nightfall, so rumbling stomachs don’t have very long to wait before breaking bread.

ANY DOS AND DON’TS?

Again, as fasting days go, this one is more casual. Keep on these leather shoes, for example: unlike on Yom Kippur and Tisha B’Av, they’re not forbidden. Neither is bathing, which, given the fact that the Seventeenth of Tammuz falls in the height of the summer heat, is a blessing. Also, special recitations—Vayechal, the very prayer that Moses offered the Lord immediately after seeing the Golden Calf, and Anenu, a traditional prayer of distress—are added to the morning and afternoon prayers.

ANYTHING GOOD TO READ?

Alas, no. With the exception of the prayers mentioned above, this is a day of reflection on sorrow and misfortune, on the destruction of the Temple and other historical horrors.

FIVE MORE THINGS YOU CAN DO:

• Get Scholarly with Yale University’s Initiative for the Interdisciplinary Study of Anti-Semitism.

• Admire Rembrandt’s depiction of Moses smashing the tablets.

• Watch as scientists struggle to authenticate a tablet pertaining to King Solomon’s Temple.

• Read the book of Zechariah, in which the fast of Seventeenth of Tammuz is mentioned.

• Prepare for fasting with some ecumenical dietary advice.