41. Blessing on the Tzitzis

9:9 One only says the blessing over tzitzis when worn by day, not by night. (The Chofetz Chaim clarifies that for this purpose, twilight is still considered daytime – see MB 18:7.) One must be careful not to recite the blessing on his tzitzis until it light enough outside so that a person can distinguish between white wool and blue wool. (Tzitzis originally had a light-blue thread among the white. A necessary ingredient used to make this dye, called techeiles, is no longer identifiable, though some feel it has been rediscovered. In the absence of blue and white wool, the test of judging whether or not it is light enough out is whether one can recognize a friend from six feet away – see Mishnah Brurah 18:9.) If one puts on his tzitzis before it gets light, or before washing his hands in the morning, with the result that he did not recite the blessing, then when he says the blessing on his tallis, he should also have his tzitzis in mind. If he does not wear a tallis, he should put his tzitzis on after daylight and after washing his hands so that he can recite the blessing “al mitzvas tzitzis,” that God commanded us regarding the mitzvah of tzitzis. If circumstances require a person to put on his tzitzis before he can say the bracha, he may take the strings in his hand and recite it after daylight. If a person slept with his tzitzis on, he may not bless over them in the morning. If he wears a tallis, he should have the tzitzis in mind when he says the blessing on his tallis.

9:10 If a person takes off the tallis with the intention of putting it back on in the near future, he does not recite the blessing when he does so. Even if he went to the bathroom in the interim, this does not constitute an interruption that would require another blessing. However, if he did not plan to put his tallis back on and changes his mind, he would say the blessing again. (This is true even if he is wearing tzitzis – see Mishnah Brurah 8:37.) If one’s tallis slipped, he would not say the blessing again while readjusting it, so long as part of it remained on him. If it fell off altogether, even if he’s still holding it in his hand, then he must say the blessing again upon replacing it, since his performance of the mitzvah was interrupted. If the tallis fell off during a part of prayer during which he may not interrupt, he adjusts it immediately but does not recite the blessing until he reaches a place where he may interrupt. He then takes the strings in his hand and says the bracha.