Reference for Shabbat 56:4

אלא לכורכן בשערן ולתופרן בגידן הא נמי הל"מ הוא דתניא תפילין מרובעות הל"מ נכרכו' בשערן ונתפרות בגידן

But Abaye said, The skin of phylacteries is a law of Moses from Sinai?<span class="x" onmousemove="('comment',' The letter shin (a) is stamped out of the leather itself at the side of the capsule. This is part of the Name Shaddai ([H]) and therefore comes within the meaning of 'the law of the Lord'. — With respect to the meaning of 'a law of Moses from Sinai', some take it literally: this was handed down direct from Moses; others understand it in a more figurative sense: it is traditional, but its exact origin is unknown, and hence ascribed to Moses, who in general is the source of Jewish law. V. Weiss, Dor, I, 71 seq. ');">⁶</span> — Rather, it is in respect of tying it with hair and sewing it with its tendons.<span class="x" onmousemove="('comment',' The parchment within the phylacteries, on which Biblical passages are written, is rolled up and tied round with animal hair. The receptacles themselves are sewn together with the tendons of animals. Both must be from clean animals. ');">⁷</span>

Explore reference for Shabbat 56:4. In-depth commentary and analysis from classical Jewish sources.