415. Beginning the Laws of Mezuzah
Tefillin, Mezuzah v’Sefer Torah 4:26
Even though the mitzvah is to wear tefillin throughout the day, it is most important to do so during prayer. The Sages said that reciting Shema without tefillin is tantamount to giving false testimony. Not wearing tefillin violates eight positive commandments because each of the four sections in the tefillin contain the commandment to wear both the head tefillin and the arm tefillin. Whoever puts tefillin on regularly will enjoy a long life, as per Isaiah 38:16, “God is upon them, they shall live.”
Tefillin, Mezuzah v’Sefer Torah 5:1
A mezuzah is written as follows: The two sections - Shema and v'haya im shamoa - are written in one column on one piece of parchment. Approximately a half-fingernail of space should be left at the top and the bottom. If a mezuzah was written in two or three columns, it is still valid so long as it was not written in the shape of a tail, a circle, or a tent. If it was written in any of these shapes, it is invalid. If the sections were written in the incorrect order, the mezuzah is invalid. If it was written on two pieces of parchment, it is invalid even if they were sewn together. A mezuzah may not be made from a Torah scroll or from tefillin that have worn out, nor may a mezuzah be written on blank parchment from a Torah scroll. This is because one may not bring something from a higher degree of holiness to a lower degree of holiness.