Why do some wear two pairs of Tefillin?

Question:

I've noticed that my Chabad rabbi dons two sets of tefillin—one during the morning prayers, and one that he puts on for a few moments right after the prayers. What is the reason for the second pair?

Answer:

Indeed, many Jews – not only Chabad – wear two pairs of tefillin.

The reason for this is that since Gaonic times (6th-11th century CE) there have been differing opinions regarding the arrangement of the four Biblical passages inserted in the tefillin boxes.

The four biblical passages written on a parchment scroll (or in the case of the head tefillin, on four different scrolls) and inserted into the tefillin boxes are: 1. "Kadesh" (Exodus 13:1-10); 2. "Vehaya ki y'viacha" (Exodus 13:11-16); 3. "Shema" (Deuteronomy 6:4-9); 4. V'haya im shamoa" (Deuteronomy 11:13-21). These are the four biblical passages that mention the obligation to wear tefillin.

In what order are these passages placed in the tefillin? Well the Talmud (Menachot 34b) records the tradition on this matter: "Kadesh and V'haya ki yeviacha to the right [of the individual opposite the tefillin wearer1]; Shema and V'haya im shamoa to the left." Furthermore, the Talmud says, if the passages are not in their proper order, the tefillin are not kosher.

The interpretation of this Talmudic rule, however, has been hotly debated.

One opinion is that "Shema and V'haya im shamoa to the left" starts from the center of the tefillin and extends left-wards. This is the opinion championed by Rashi, an eminent 11th century sage.

Rashi's Tefillin:

The other opinion maintains that "Shema and V'haya im shamoa to the left" starts from the left edge of the tefillin and extends inwards. This is the opinion supported by Rashi's grandson, known as "Rabbeinu Tam."

Rabbeinu Tam's Tefillin:

The Code of Jewish Law sides with Rashi's opinion. Nevertheless, it says that "all G‑d fearing individuals"2 should have two pairs of tefillin and wear both each day. In chassidic circles it is especially common to wear two pairs of tefillin, this because according to kabbalah it is important to wear both pairs, each one representing a different divine flow of energy.

Rabbeinu Tam's Tefillin are donned after the morning prayers,3 without the recitation of a blessing. While wearing them, it is customary to recite the three passages of the Shema, as well as the Kadesh and V'haya ki y'viacha passages.

Yours truly,

Rabbi Menachem Posner