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?

Synopsis

The Mishnah Berurah, citing the Arizal, rules that the Rashi tefillin go on the bottom (closer to the face/skin) and the Rabbeinu Tam tefillin on top (toward the hand). The Rashi tefillin should be larger, and the RT straps concealed beneath the Rashi straps.

Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

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