1) MOVING "MUKTZAH" WITH ONE'S BODY
OPINIONS: The Mishnah states that one may use his body, but not his hands, to move straw that is on a bed, even though the straw is Muktzah because it is designated as fuel for fire (Rashi DH ha'Kash). Why is one permitted to move straw with one's body if the straw is Muktzah?
(a) According to RASHI, the person is permitted to move the straw with his body in order to arrange the straw such a way that he will be comfortable when he reclines on it. Perhaps Rashi rules like the ROSH (3:19), who permits one to move Muktzah with his body as long as he does not move it with his hands. (It is possible, however, that Rashi permits one to move Muktzah only with the trunk of his body, but not with his feet, which he sometimes uses to move objects.)
(b) The RITVA (44a) explains that one is permitted to move straw that is Muktzah in this case because the person does so in order to rest on Shabbos. For one's Shabbos pleasure, he is permitted to move Muktzah with his body.
(c) The RAN, RAMBAN (44a), and the RITVA later (154a) explain that the Mishnah refers to one who wants to lie down on the bed but the straw is in his way. He may knock the straw off of the bed, because he moves it for the sake of something which is permissible (the bed). (This understanding of the words of the Ramban is printed at the end of Shemiras Shabbos k'Hilchasah in the name of Rav Shlomo Zalman Auerbach zt"l.)
(d) The CHAZON ISH interprets the RAMBAN's words differently. According to his understanding, the Ramban means that one may move the straw because he is not doing an obvious, visible act of moving the straw. Rather, while in the process of the act of lying down he moves the straw out of the way. (See also Insights to Shabbos 127:1.)
2) HALACHAH: WIPING MUD OFF OF ONE'S SHOES
OPINIONS: The Gemara records a four-way dispute with regard to wiping mud off of one's shoes on Shabbos. Abaye permits one to rub the shoe against the ground in order to remove the mud, but not against a wall. Rava gives the opposite ruling: one is permitted to rub the shoe against a wall, but not on the ground. Mar brei d'Ravina prohibits both, and Rav Papa permits both. What is the Halachah?
(a) The RIF rules that rubbing one's shoes on the ground and on a wall is prohibited (like Mar brei d'Ravina).
(b) The RAMBAM rules that one may not rub one's shoes on the ground, but one may rub them on a wall (like Rava).
(c) The ROSH rules that both are permitted, because this is a Safek d'Rabanan in which case we are always lenient.
HALACHAH: The SHULCHAN ARUCH (OC 302:6) cites the first two opinions (those of the Rif and the Rambam), and the REMA cites the third opinion (that of the Rosh). The MISHNAH BERURAH rules (for Ashkenazim) that one should be stringent and favor the compromise opinion of the Rambam, that one may not rub one's shoes on the ground but one may rub them on a wall.

141b----------------------------------------141b

3) REMOVING TERUMAH FROM A MIXTURE
QUESTION: The Mishnah discusses moving items that are Muktzah, such as a stone and Terumah Teme'ah. The Mishnah continues with a statement of Rebbi Yehudah, who says that a person may remove produce from a mixture of Terumah which fell into Chulin, and, if the Terumah became Batel, one need not worry that he is performing an act of Tikun on Shabbos ("fixing" the Chulin by removing the prohibited Terumah that fell into it).
In what way is Rebbi Yehudah's statement related to the rest of the Mishnah, which discusses the laws of moving Muktzah?
ANSWER: The SEFAS EMES suggests that perhaps Rebbi Yehudah's statement refers to Terumah Teme'ah that fell into Chulin and became Batel. Since the portion of produce that one removes is considered to take the place of the Terumah that fell in, it must be burned like any Terumah Teme'ah. Perhaps Rebbi Yehudah is teaching that even though the portion that one removes is considered Terumah Teme'ah after one lifts it out of the mixture and it is Muktzah, nevertheless one is permitted to take it out because at the moment that he lifts it up it is not Terumah Teme'ah. (The Sefas Emes remains in doubt whether or not this approach is Halachically accurate.)

OTHER D.A.F. RESOURCES
ON THIS DAF