What the Small Boxes Contain
The cases are called tefillin (often called phylacteries in English). Inside are narrow strips of parchment bearing handwritten passages from the Torah, including verses that instruct Jews to bind these words as a sign on the hand and between the eyes. The head tefillin holds the passages in separate compartments; the arm tefillin holds them together in one.
The words are not meant to be read through the cases. Their placement turns the biblical instruction into a physical practice: one box rests on the forehead, while the other is secured to the upper arm with a leather strap.
Why They Are Worn
Tefillin are traditionally put on during weekday morning prayer. The arm box is placed on the nondominant arm, and the strap is wound around the arm and hand. The head box is positioned above the forehead, with its strap extending around the head. Details of the ritual can vary among Jewish communities.
The paired placement gives the practice its meaning. The arm is associated in the ritual with action, and the head with thought; the Torah passages are thus kept close to both. For wearers, the straps do more than hold the cases in place: winding them is part of carrying out the commandment.
A Portable Reminder
Tefillin are generally not worn on Shabbat or major Jewish festivals, when the daily obligation is understood differently. On an ordinary weekday, however, the ritual makes prayer tangible: parchment containing sacred text is fastened to the body, and the act of putting it on becomes part of the morning itself.
