Must a new blessing be recited if tefillin slipped from their proper place and were repositioned?

Synopsis

The Mechaber rules a blessing is required when tefillin slip and are repositioned. The Rema disagrees for the case of intentional removal with intent to replace. The Shela explains why Ashkenazi practice does not recite the blessing even when tefillin slip — since during prayer one presumably has not taken his mind off them.

Early Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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