Halakhah for Yoma 142:15

מעיל שנים עשר מנא לן דכתיב (שמות כח, לא) ועשית את מעיל האפוד

One may infer from the analogy of 'twined' used in connection with the curtain: just as there [each twined thread] was twenty-four-fold,<span class="x" onmousemove="('comment',' [The curtain had four kinds of material, each having its thread sixfold, since the word shesh is mentioned in connection therewith, v. Ex. XXVI, 31. Thus each twined thread which consisted of the four materials was twenty-fourfold].');">¹⁸</span> so also here was it twenty-four-fold, the thread of each kind of material being eightfold.<span class="x" onmousemove="('comment',' I.e., with the robe where only three kinds of materials were used, the threads of each strand had to be eightfold to make each twined thread of all the material twenty-eightfold].');">¹⁹</span> - But one should infer from breast-plate and apron: just as there it was twenty-eightfold, so also here twenty-eight-fold?<span class="x" onmousemove="('comment',' As shewn infra.');">²⁰</span> - One may infer a thing in connection with which gold is not mentioned from another thing, in connection with which gold is not mentioned;<span class="x" onmousemove="('comment',' I.e., the robe from the curtain neither of which had gold.');">²¹</span> that excludes the breast-plate and apron in connection with which gold is mentioned. On the contrary! One should, rather, infer concerning one garment from another garment, which would exclude the curtain, because that [in a sense] is a tent! - Rather, if it is inferred from the girdle,<span class="x" onmousemove="('comment',' [Which also had four kinds of material each of sixfold threads, since shesh is written in connection therewith, v. Ex. XXXIX, 29].');">²²</span> thus inferring concerning a garment, in connection with which gold is not mentioned from another garment, in connection with which gold is not mentioned; but not inferring concerning anything, in connection with which gold is mentioned from something in connection with which gold is mentioned. R'Mari said: Scripture said: Thou shalt make it,<span class="x" onmousemove="('comment',' Ex. XXVIII,15 is with reference to the breast-plate.');">²³</span> i.e., only, nothing else.<span class="x" onmousemove="('comment',' Only breast-plate and apron, 'it', hence no precedence for any other garment, taking 'it' to indicate 'it' exclusively.');">²⁴</span> R'Ashi said: And thou shalt make,<span class="x" onmousemove="('comment',' Ex. XXVIII, 33, repeated in connection with the pomegranates, indicates that all the material used there must have been made alike. Hence it is impossible for the twined thread in the robe to be of a twenty-eightfold, as he goes on to explain.');">²⁵</span> i.e., all the work in connection therewith must be the same. Now how is that possible? If he were to make the three kinds tenfold each, there would be thirty [threads]. And if one made two ninefold and one tenfold, but Scripture said: 'And thou shalt make', i.e., all the work in connection therewith must be alike. Whence do we know that the robe [had its threads] twelvefold? Because Scripture said: And thou shalt make the robe of the ephod

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