Hello kollel!
I'm on of the weekly shiurim of r Moshe shapira he mentioned that in the desert before Moshe spoke devarim their tefillin had only 2 parshiot.
Is that correct? Is it not meakev, or conversely if you need all 4 did the mitzvah only start at the end of the time in the desert?
Thank you,
Josh
Shalom Josh,
This is an excellent question! Indeed, several commentaries deal with this question. The most prominent view that I could find that firmly adopts the view that Yidden who wore Tefilin in the Midbar would have only 2 Parshiyos is the Klei Chemdah (Devarim #3 DH ub'Emes; va'Eschanan #6 Amnam b'Ikar).
On the other hand, the commentary attributed to the Rashba (Menachos 34a DH u'Mah Talmud Lomar) -- although many say this was actually written by the Tosfos Rid -- concludes that even in the Midbar Tefilin must have included all 4 Parshiyos.
Again, other great commentaries discuss this question; for example, the Mabit. So, of course, this matter can be purused further if necessary.
Warmest regards,
Yishai Rasowsky