The 17th of Tammuz

On the 17th of Tammuz five major tragedies befell the Jewish people: 1) Moshe broke the tablets of the Ten Commandments; 2) the Daily Sacrifices (Korban Tamid) were suspended; 3) the Romans breached the walls of Jerusalem - leading up to the destruction of the second Temple; 4) Apostomus (a Roman general) burned the Torah; and 5) an idol was erected in the Temple.

As a result, the 17th day of Tammuz was designated as a fast day, and for Ashkenazim, it is also the beginning of the three week period of national mourning for the destruction of the Temples. (Interestingly, there is a dispute whether or not the “three weeks” begins the night of the 17th of Tammuz [Tzitz Eliezer 10:27] or in the morning [Iggrot Moshe Orech Chaim vol. 1:168]. However, unless there is a pressing need to be lenient, the general consensus is to consider the night of the 17th as the beginning of the three weeks.)

Some Laws of this Fast Day:

The fast begins 72 minutes before sunrise (4:24 am) and continues until the end of the day (30 minutes after sunset is 8:38 pm). Food and drink may be consumed any time during the night, as long as one has not gone to sleep "for the night".

Although it is permitted to bathe on a fast day, it has become customary not to take a hot shower or bath [Aruch haShulchan 550:3].

The rabbis differ as to whether it is permitted to rinse one's mouth with water on the fast days such as this [Shulchan Aruch, Orech Chayim 567:3]. Some permit rinsing the front part of the mouth and even brushing one's teeth, taking care that no water enters the throat [Aruch haShulchan 567:3], while others allow this only when in distress [Mishna Berurah 567:11].

Medications PRESCRIBED BY A DOCTOR may be taken on this fast day. If one has difficulty swallowing pills without water s/he may drink a small amount of water required to swallow the medicine [Nishmat Avraham, vol. 5, pg. 46 in the name of Rabbi S.Z. Auerbach].

There is a debate among authorities whether pregnant or nursing woman should fast on the 17^th of Tammuz (and the other minor fast days). Some maintain that they should, unless they are in significant discomfort [Chayyei Adam 133:6] or feeling weak [Mishna Berurah 550 note 5]. While the Aruch HaShulchan (among others) exempted them from fasting on these days [Aruch HaShulchan 554:8, Halichot Beitah 25 note 3]. 

This year, because the 17th of Tammuz is on Shabbat, and the fast is being observed a day later on Sunday, one may be more lenient both in terms of pregnant and nursing women and for those who are ill [Shvut Yaakov 3:37 and Nitei Gavriel 6:9.

If by accident, a healthy person ate some food, the fast should be resumed and completed as normal [Mishna Berurah 549:3].