On which side of the klaf (parchment) must tefillin be written, and what are the requirements for the type of parchment?
Synopsis
It is a halacha l'Moshe miSinai that tefillin must be written on klaf (the outer layer), on the flesh side (the inner surface of the klaf). Writing on dukhsustos or gevil, or on the wrong side, is invalid.
More in Writing Tefillin
Must the four Torah passages for tefillin be written in the order they appear in the Torah, and is tefillin written out of order invalid?
4 opinions
Should the arm-tefillin passages be written before the head-tefillin passages, or does it not matter?
3 opinions
Must the head-tefillin's four passages each be written on a separate parchment, while the arm-tefillin's four passages are written on a single parchment?
1 opinions
Must tefillin be written with black ink, and does writing even one letter in another color or in gold invalidate the tefillin?
2 opinions
Must each letter in tefillin be completely surrounded by parchment and not touch another letter?
2 opinions
Must tefillin be written with the right hand, and are tefillin written with the left hand invalid?
2 opinions
How many lines must be scored (ruled) when writing tefillin, and may lead be used for scoring?
3 opinions
Must the parchment be processed (tanned) with the specific intent (lishmah) of making it for tefillin, and what is the requirement for verbal declaration?
1 opinions
Related from other topics
On which hand does a left-handed person (ittir) wear tefillin?
How to Put On Tefillin
Which tefillin should be removed first when taking off tefillin?
What Invalidates Tefillin
Must Tefillin straps (retzuot) be black, and on which side?
Tefillin on Chol HaMoed
When wearing both pairs of tefillin simultaneously, what is the correct physical arrangement — which pair goes closer to the skin and which on the outer side?
Tefillin of Rabbeinu Tam
According to Kabbalah (the Zohar and Arizal), which arrangement of tefillin parashiyot is correct?
Tefillin of Rabbeinu Tam
How many lines (shitin) should be written on each parasha of the hand tefillin parchment?
Tefillin Parchment Line Arrangement
Discussion
Discussion coming soon.
The Daily Law
One question. Every opinion. Every morning.
A new halakhic question and the full spectrum of rabbinic thought, delivered daily.