Hilchos Tefillin

  1. Because of the great sanctity of Tefillin, great care should be taken to
    prevent them from falling on the floor. If they do fall, the custom is to
    fast. If they are still in their pouch, it is sufficient to make a donation to
    charity. Fasting, or a donation to charity, is required even when they fall by
    accident, for the very fact that they fell is regarded as a sign that the
    person who dropped them should do teshuva.
  2. Regarding this halachah, there is no difference between Tefillin placed on
    the arm and Tefillin placed on the head, or between the Tefillin of Rashi and
    Rabbeinu Tam. There are those who fast even if the parshios alone fall on the
    floor. Nevertheless, when a mezuzah falls on the floor it is customary to give
    a small donation to charity rather than fast.
  3. If the straps of the Tefillin fall on the floor, even though care should
    be taken to prevent it, it is not customary to fast.
  4. According to the Admor of Belz, the custom of fasting also applies when
    Tefillin fall to the ground while covered by their case (usually made of
    plastic) because the knot of the Tefillin is outside the case and, in contrast
    to the rest of the strap, the sanctity of the knot is comparable to the
    sanctity of the Tefillin. If the empty pouch falls to the ground, neither
    fasting nor charity is required.
  5. The custom of fasting applies even when the Tefillin fall from a height of
    less than ten t’fachim
    (about
    1 meter).
  6. One need not fast when Tefillin fall onto the surface of a table. If
    Tefillin fall onto the stairs that ascend to the Aron HaKodesh, it is as
    though they fell on the floor.
  7. If a person drops his Tefillin, when should he fast? If he did not yet eat
    or drink, he should fast on the day that the Tefillin fell, even though he did
    not accept upon himself to fast on the previous day. But if he already ate or
    drank on that day, he should fast on the following day.
  8. Because of the weakness of the generation, many observe the custom of
    fasting until noon, even if they drank before the morning prayers. Those for
    whom the fast is difficult (especially if it would disrupt their Torah
    learning) redeem it with a donation to charity.
  9. According to some, the owner of Tefillin that fell should make a donation
    to charity, even when the Tefillin do not fall from his hand, for he was
    negligent in putting them in a place from which they might fall. A person who
    sees another’s Tefillin fall is not required to fast.