
For those who don't know what the Tefillin is, it is a Jewish prayer ritual object.
It is a container for the a Shema, a passage starting from Deuteronomy 6:7, to be spoken by devout Jews three times a day. The V'ahavtah, usually spoken at the same time, says these words, "bind them as a sign upon your hand and as a reminder above your eyes." Hence Tefillin.
The paper, ink, and calligraphy of the words therein are carefully controlled.