Is it permitted to convert head tefillin into hand tefillin when a prior stipulation (tenai) was made?

Daily LifeTzitzit & TefillinTefillin

Synopsis

The Mechaber rules that if a stipulation was made at the time of making the tefillin allowing future conversion, they may be converted even from head to hand tefillin even after they have been worn. The nature and timing of the stipulation is debated.

Early Acharonim
Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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