From the Rav’s Desk: Is fasting today optional or obligatory?

1. Question: [Thursday, 17^th Tamuz, 5783]

I heard someone quote that in today’s times fasting is no longer obligatory and is only a custom? Is there any truth to this?

Answer:

While this may be theoretically accurate, it is practically false, and all Torah observant Jews are obligated to fast by each one of the four fast days enacted by our sages unless they fall under one of the exception categories, such as if they are sick, pregnant nursing after birth etc. etc.

Explanation:

The Talmud states that when the sages originally established the rabbinical fast days they only made it obligatory to fast on these days during times of danger. However, when there is peace in the world then they did not require anyone to fast, and it is rather voluntary. [This Talmudic letter of the law was mentioned and explained in one of the Rebbes later talks, however not G-d forbid in negation of the practical ruling and custom.] Despite this Talmudic ruling, as in all matters in Jewish law, we take into account the final custom of the Jewish people and the final ruling in the Shulchan Aruch and Poskim, which states that the custom is to fast on the above fast days even during times of peace and that it is forbidden for one to swerve from the custom and not fast. This can be viewed similar to the prayer of Maariv which is although technically a voluntary from a Talmudic perspective, it is practically an obligation being that we have taken it upon ourselves to pray it, and the same applies regarding the fast days.

Sources: See that everyone today must fast on a Taanis Tzibur until the coming of Moshiach, and it is forbidden to be Poretz Geder: Michaber 550:1; M”A 550:1; Tur ibid; Ramban in Toras Hadam; Beis Yosef 550; Maggid Mishneh Taanis 5; Rishonim and Poskim brought in Machatzios Hashekel 550:1; Mateh Yehuda 550; M”B 550:1; Kaf Hachaim 550:3 See that from the letter of the law, the Sages  established all the fasts, other than Tisha B’av, as obligatory only in a time of danger: Rosh Hashanah 18b, brought in Tur 550 and Machatzis Hashekel 550:1; Sichas 17 Tamuz 5751