Why do some people wrap their Tefilin around their arms 8 times?

I have seen people who wrap the Tefilin 7 times around their arm and some that wrap it 8 times around their arm. Why do the people who wrap it 8 times do so?

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Probably cause there is no Halakha about warping so like all things that are only customs diffident Jews HAVE to do things differently lol. But really, I was taught to wrap it around my arm as many times as one needs to get the right length. I personally wrap it 7 times (including the the wrap that goes from the bicep to the fore arm, But in my community people do it any were between 5-8 times depending on their arm and strap length. – Qoheleth Sep 13 '12 at 19:40
My father is Persian, but he always put on seven, as the man who taught him was Sudanese. At my Bar Mitzvah a Persian cousin of mine and my grandfather came up to me and they taught me that many or most Persians have the custom of wrapping eight times. You may have seen Persians doing it. Otherwise, I can't help you. – user9561 Jun 7 '15 at 1:58

The part of the arm that matters when counting the number of loops around the arm is from the elbow to the wrist. The Chabad custom is to wrap the straps so that there are 6 complete loops and 2 half loops. This equals 7 complete loops, but may look like one is wrapping 8 loops.

As you can see from this picture from Chabad.org's article about Tefillin, the view of the inner arm and outer arm both have 7 loops between the wrist and the elbow. However, the view of the inner arm is 2 loops, a space, and then 5 loops, while the view of the outer arm is 3 loops, a space, and then 4 loops.

This is because the first and last loops are only 1/2 way on the arm (between the elbow and the wrist), and are only visible on one side (of that part of the arm), respectively.

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interesting ive never seen that king of wrapping style before , thanks for the pictures. – Qoheleth Sep 13 '12 at 19:42

I wrap it seven times, but have been told I wrap it eight times because people count differently than I. That is, from the elbow, I wrap it half a time, seven full times, and whatever's necessary to bring it around again (i.e., another half). So it's seven, see? No, really. Seven. Count 'em.

No, count 'em this way. `:-)`

As to why I put the extra halves, I don't know, except that my father does (and, presumably, his father did, and his father, etc.).

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I don't know about 8 times, but the Shulchan Aruch OC 27:8 says

ונוהגין העולם לכרוך על הזרוע ששה או שבעה כריכות

The custom is to wrap [the strap] around the forearm 6 or 7 times.

It seems not only that we should be discussing 6 or 7 and not 8, but also that the exact number doesn't really matter.

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Never saw six.. – Gershon Gold Jan 15 '12 at 19:17
@GershonGold because Arizal says seven (at least for Sefardim that may be why). – Hacham Gabriel Jan 17 '12 at 1:36

Can't remember the source, but I remember seeing somewhere to wrap 8 times around the arm. Be'ezrat HaShem Beli Neder source coming soon.

As Msh210 wrote up there it is really 7 with an extra half (see Siah Yitzhak Siman 5): ועל הזרוע שמונה כריכות, כי כריכה ראשונה אינה במילואה ואינה נחשבת

The first one doesn't count because it is incomplete.

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Searching for that title on hebrewbooks.org yields some sixteen different books by some sixteen different authors (not to mention any that aren't on that site). Do you think you could be more specific, please? (Even better would be a hyperlink.) – msh210 Jan 15 '12 at 17:41
I'm not really sure because I found it on the Responsa.Co.il of Bar Ilan :) – Hacham Gabriel Jan 15 '12 at 17:43
This parshah leaflet sources it to Baal Shem Tov al ha-Torah. – Alex Jan 15 '12 at 18:07

In addition to the Minhagim mentioned, it also is closely related to the direction one wraps. Wrapping inward tends to make it obvious how many loops there are, whereas wrapping outward leaves it unclear, hence the need for different Minhagim (6 and 2 halves, 7 and a half, etc.) to make an extra loop to ensure 7 complete loops.

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