Reference for Eruvin 205:22

רבא אמר רבי אליעזר היא דאמר מכשירי מצוה דוחין את השבת ומודה ר' אליעזר דכמה דאפשר לשנויי משנינן

remained silent. When he? came to R'Joseph and told him 'Thus said R'Safra to me, the latter asked him: Why did you not answer him, 'The members of a [paschal lamb] party<span class="x" onmousemove="('comment',' Who joined to participate in the paschal lamb which, like other sacred food, required careful attention.');">⁷³</span> are careful'?<span class="x" onmousemove="('comment',' And no preventive measures in their case are needed.');">⁷⁴</span> - And Abaye?<span class="x" onmousemove="('comment',' How is it that he overlooked this distinction?');">⁷⁵</span> - We only presume that priests<span class="x" onmousemove="('comment',' Who from their youth are trained for the Temple service.');">⁷⁶</span> are careful, but we do not presume that the members of a [paschal lamb] party<span class="x" onmousemove="('comment',' Who are mere laymen.');">⁷⁷</span> are also careful. Raba<span class="x" onmousemove="('comment',' Maintaining that both Mishnahs deal with the case of removal by hand of a soft wen. The Mishnah of Pesahim cannot refer to removal by means of an instrument, on account of the objection raised supra that such a removal would be an act Pentateuchally forbidden; and our Mishnah cannot refer to a dry wen which may be removed even by means of an instrument since, in its final clause the use of an instrument is forbidden.');">⁷⁸</span> explained: This<span class="x" onmousemove="('comment',' The ruling in our Mishnah which permits the removal of a wen by hand, which is shebuth that could have been performed prior to the Sabbath.');">⁷⁹</span> represents the view of R'Eliezer who<span class="x" onmousemove="('comment',' Besides differing from the Rabbis in the Mishnah of Pes. in the case of a shebuth.');">⁸⁰</span> ruled that the preliminary requisites of a precept supersede the Sabbath,<span class="x" onmousemove="('comment',' Even where one of the main classes of work that are Pentateuchally forbidden has to he performed, and much more so, as is the case in our Mishnah and in that of Pes., where only a shebuth is involved.');">⁸¹</span> R'Eliezer however, agreeing that a change<span class="x" onmousemove="('comment',' In the manner of their performance or preparation.');">⁸²</span> should be made as far as this is possible.<span class="x" onmousemove="('comment',' As it is possible to remove a wen by hand he ruled in the final clause of our Mishnah that the use of an instrument is forbidden. Where, however, no change is possible, even one of the mail classes of forbidden work supersedes the Sabbath.');">⁸³</span>

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