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 The proper wording of sefiras ha'omer The Mechaber writes out the proper wording to be said for sefiras ha'omer.  "Today is one day..." is followed by "Today is two days..." etc., until the seventh day, when the words "which is one week" are added. On the eighth day we say "Today is eight days, which is one week and one day...", and the rest of the days and weeks are counted in a similar manner. The Rama adds the word ba'omer at the end of each phrase. The Mishnah Berurah observes that most poskim spell the word with a lamed - la'omer and this, indeed, is the version of the Arizal. Nevertheless, the Gra and Chazon Ish stick with ba'omer. In an effort to fulfill both customs, there are people who count twice - once with la'omer and once with ba'omer. (סעיף א וס"ק ח; ביאורים ומוספים דרשו, 30)
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 Hilchos Tzitzis 11 (page 45)
 Coiling the Lead String Around the Others Dangling the Strings Over the Corner Reinforcing the Corner
 Coiling the lead string around the others We learned yesterday that between the five double knots of the tzitzis are four sections where one thread is wrapped around the others. In each section, the lead thread is coiled around the others a different number of times. According to the Mechaber, the numbers for each section are: seven, nine, eleven and thirteen. Altogether the sum is forty, which equals the numerical value of Hashem's name (26) plus the value of the word echad (13) plus one. According to the Arizal, the numbers for each section are: seven, eight, eleven and thirteen. The coils equal thirty-nine, corresponding to the numerical value of Hashem's name plus the numerical value of echad. The Acharonim recommend following the Arizal. (סעיף יד וס"ק ע)
 Dangling the strings over the corner Ideally, the tzitzis strings should be arranged to dangle over the corner and not to hang from the bottom. The method of accomplishing this depends on how the garment is worn. Generally, it means that the strings should be drawn across the side of the garment to hang from the side and not straight down. B'dieved, the strings are kosher if they hang from the bottom. It is important, though, that the strings not run diagonally across the talis to hang from the point of the corner, because that is the style of the Karaim. (סעיף טו, ס"ק עב ו־עג, וביה"ל ד"ה לאורך; ביאורים ומוספים דרשו, 85)
 Reinforcing the corner According to some poskim, a patch of material different from the rest of the talis should not be attached underneath the corners of the garment (e.g. for reinforcement). One reason for this is that the Torah states "on the corners of their garments," implying that the tzitzis should rest directly on the garment and not on an extra piece. The second reason given is that Chazal understood the pasuk "the tzitzis of the corner" to mean that the tzitzis should match the material of the garment, which can't be done if the corner is made of two materials. (The exception to the matching rule is wool and linen, which are acceptable materials to be combined in this case.) Others hold that a patch stuck onto a garment is batul to it and does not interfere. The custom is to permit adding a patch under the corners of the garment. (סעיף טו, ס"ק עד ו־עה, וביה"ל ד"ה שאין)

 The Torah uses the words gedilim (braided) and pesil (doubled) when talking about the mitzva of tzitzis. Gedil implies two strings braided together and gedilim implies two more. Pesil tells us that these four strings should then be folded over when inserted into the garment. In all, there are four strings that are doubled when inserted into the corner holes to make eight. If fewer than four strings were used on a corner, the tzitzis are pasul. Likewise, if more than four were used they are pasul and also a violation of ba'al tosif Mid'oraisa, all that is required is one double knot on top, three coils, and then a second double knot to hold the coils in place. Mid'rabonon, there should be five [doubled] knots to represent the five chumashim. The opinion of the Rosh regarding torn tzitzis strings The length of "kdei aniva" Repairing a torn string
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