Commentary for Menachot 66:7
תנא העמיד לה מלבן של קנים חותך שפופרת ומניחה אמר רב אחא בריה דרבא לא שנו אלא שהעמיד ולבסוף חתך והניחה אבל חתך והניח ולבסוף העמיד פסולה תעשה ולא מן העשוי
R'Aha the son of Raba said, This was taught only if he first set up the door-frame and then cut away a length of reed and placed [the mezuzah] therein; but if he first cut away a length [of the reed] and placed therein [the mezuzah] and then set up [the whole as a door-frame], it is invalid, because of the principle 'Thou shalt make, but not [use] what is ready made'.<span class="x" onmousemove="('comment',' The principle stated here, which is derived from the law of sukkah (v. Deut. XVI, 13) and of zizith (v. ibid. XXII, 12) , where in both texts the expression 'thou shalt make' is used, is that one's duty is fulfilled only when the precept has been performed after the obligation for its performance has fallen due. In this case, however, the mezuzah was fixed to the door-post before the latter had been set in position and then there was no obligation for a mezuzah; therefore when later it is set in position the mezuzah is 'ready made' and cannot serve the purpose. hj,p');"><sup>5</sup></span> Raba also said, Faulty<span class="x" onmousemove="('comment',' 'Semitic doors' (R. Han. in Tosaf. 'Erub. 11a, s.v.) .');"><sup>6</sup></span>
Explore commentary for Menachot 66:7. In-depth commentary and analysis from classical Jewish sources.