Fallen Mezuza

Question: One of our mezuzos got knocked off accidentally. Do we need to fast?

Answer: The Magen Avraham (44:5 quoting the Mishpatei Shmuel) and Shulchan Aruch Harav (OC 44:5) write that there is a minhag for one to fast if their tefillin fall on the floor. According to the Mahari Brunna (127) one who drops their tefillin should see it as a sign from heaven that they need to do teshuva. The Chida (Chaim Sha’al 1:12), however, explains that one must do so to atone for not treating them with the due care and respect (see Tzitz Eliezer 5:1).

R’ Moshe Zvi Landau (Mezuzos Melachim, Halacha Lemoshe 201) writes that there is a machlokes as to whether one needs to fast or not if a mezuza falls. R’ Moshe Leib Rosenbaum (Beis Aryeh 15:6) writes that one does need to fast, while R’ Chaim Falagi (Lev Chaim 3:131) maintains that one does not need to fast as a mezuza is not as holy as a sefer Torah or tefillin (see Maharsham 2:264).

R’ Moshe Stern (Baer Moshe 3:9:8), R’ Menashe Klein (Mishne Halachos 5:195) and R’ Shraga Feivish Schneebalg (Shraga Hameir 3:12:1) write that this minhag to fast does not apply when a mezuza falls. Rather than fast, one should donate money to tzedaka.

The Chida concludes that each Rav should decide what is appropriate for his kehilla.

In conclusion, one does not need to fast if their mezuza fell to the ground.