Question:
Why in chol hamoed of pessach is not used tefilin?
Answer:
There are different minhagim regarding this, those who have the minhag not to is because Chol Hamoed which is part of Yom Tov is also considered an “os” symbol, and we don’t wear tefillin which is a also considered a symbol, because we already have it on Chol Hamoed.
Gut moed
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