Can I check my Tzitzis on Shabbos?
One is supposed to check his Tzitzis every single day before he makes a Brocho on it, both the Tallis Koton and the Tallis Godol. Even if one has no other Tallis available, he should still check his Tzitzis every single day, including on Shabbos. Of course on Shabbos, one can’t fix the knot. Therefore some people prefer to check it on Friday when they could still fix it. One should be careful on Shabbos when he checks the Tzitzis to hold them down in such a way as to help him remember not to make a knot on Shabbos. Fixing the Tzitzis can be done even in the Mikvah. In the morning when one is putting on his Tallis Koton in the Mikvah, he can check it there and look at it carefully, and he is allowed to make the knots in the Mikvah as well. Some people, however, prefer not to do it in the Mikvah, only when they come out afterwards.
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