Someone has an older pair of batim for tefillin that were once used however are now pasul. May they be used now to teach with? The shailo is since the person will be cutting them, putting holes in them, sanding it down more perhaps, etc. Since they were already used for the mitzvah perhaps this is a problem? Please provide any sources.
Answer:
There is no problem of using them for teaching.
The fact they were used for a mitzvah, and moreover the fact that they were used to house the parshios, means that they possess kedushah, but this means that they must be treated with respect, and what greater respect is there than use in teaching?
I therefore don’t see any problem in this.
If the tefillin require sanding etc. the cut parts should not be thrown away but treated with kedushah (put in genizah, or given to a battim-macher for use in other tefillin).
Best wishes.
