Gemara

Rabah and R. Zeira visited the Reish Galusa's house [on Shabbos]. A slave spread a turban over a flask and put a ladle on top. Rabah rebuked him.

The slave later squeezed out water absorbed in the turban.

Question (R. Zeira): Since people may come to squeeze, why do Chachamim permit spreading a cloth over a flask?

Answer (Rabah): We are not concerned lest one squeeze a cloth, for people do not care if it is wet. However, people do not want a turban to be wet.

143a (Mishnah): If a sponge has a leather handle, one may clean with it. If not, it is forbidden [lest he squeeze].

In either case one may take it on Shabbos. (Some texts - Chachamim say, in either case one may use and take it on Shabbos.)

Inference: This (the Reisha) is like R. Yehudah, who forbids Devar she'Eino Miskaven!

Rejection: It is even like R. Shimon;

(Abaye and Rava): R. Shimon agrees regarding a Pesik Reishei.

143b (Mishnah): If a barrel broke, one may save food for three meals, as long as he does not soak up.

(Beraisa): One may not soak up wine, and one may not wet his hand in oil, for this is Uvda d'Chol (like one does on a weekday).

Rishonim

Rambam (Hilchos Shabbos 22:15): One who squeezes is liable, for this launders. One may not clean with a sponge unless it has a leather handle, so he not squeeze.

Ra'avad: Chachamim of France explain like this. (See Rashi below.) This is difficult. What difference does it make if it has a handle? One cannot clean without squeezing! I say that since there is a handle, it is like a plate full of water from which one pours out water. When there is no handle, it is like a garment and it is forbidden to squeeze it.

Magid Mishneh: The Rambam holds like Rashi (below DH Ein).

Rambam (16): If a barrel broke on Shabbos, one may not soak up wine, and one may not wet his hand in oil, for if he does like on a weekday, he might come to squeeze.

Magid Mishneh: Rashi says that one may not put a sponge where the wine is with intent to let it drip into a Kli, lest he come to squeeze. One may not wet, i.e. insert his palm in oil, and the oil will stick to it [and scrape his palm against the wall of a Kli so the oil will drip inside.]

Rashi (143a DH Ein): When he holds the sponge, it is squeezed between his fingers.

Rashi (143a DH Nital): One may move the sponge when it is dry.

Poskim

Shulchan Aruch (OC 320:15): One may not spread a turban over a flask and put a ladle on top, lest he come to squeeze.

Mishnah Berurah (42): Squeezing a garment is liable for laundering. If the flask contains liquid, in any case one may not spread a turban over it, lest he come to squeeze, even if he will not put a ladle on top.

Shulchan Aruch (ibid.): One may spread over a flask a garment that he normally spreads over it, for he is not concerned for it to squeeze it [if it gets wet].

Mishnah Berurah (43): This is permitted only in a way that there is no concern for Ohel (making a covering over the flask).

Shulchan Aruch (17): One may not clean with a sponge unless it has a handle. This is a decree lest he squeeze.

Beis Yosef (DH Sefug, citing the Magid Mishneh): The Ra'avad asked, what difference does it make if it has a handle? One cannot clean without squeezing! I say that since there is a handle, it is like a plate full of water from which one empties out water.

Drishah (2 DH Kasav): The Beis Yosef says that one may not clean with a sponge unless it has a handle. This is a decree, lest he squeeze. He connotes that the Magid Mishneh answers that when it has a handle, it is like pouring from a plate. Really, these are the Ra'avad's words! Also, the Beis Yosef connotes that the Ra'avad questions the Gemara. Really, he questions only the Rambam, who permits only when it has a handle, so he will not squeeze. The Ra'avad disagrees. Surely he squeezes, but the squeezing does not harm, for he does not squeeze between his fingers. Rather, it is like pouring from a plate. Really, one can explain the Rambam's words 'so he will not squeeze' to explain why one may not squeeze with a sponge. It is not difficult for the Tur and Rashi. Perhaps the Beis Yosef brought the Ra'avad merely to teach about the Tur and Rashi.

Levush (17): One may clean with a sponge only if it has a handle. This is a decree lest one squeeze between his fingers. Even though it is a Pesik Reishei even when it has a handle, when it comes through a handle it is not called squeezing. It is like pouring from a full Kli. It is unlike laundering. See 335:1 (below).

Magen Avraham (19): Since a sponge is made for squeezing, why do we decree lest he squeeze? Sa'if 15 permit a cloth normally spread over a barrel, for he does not care if it becomes soaked! Also in 301:41 we permit (drying with a towel). Also, the Gemara asked about a sponge 'we hold like R. Shimon, who permits Davar she'Eino Miskaven', and answered that it is a Pesik Reishei. If so, it is not a decree! This requires investigation. The Ra'avad holds that one cannot clean without squeezing. If so, why did Chachamim permit to clean with a towel? We must say that only with a sponge it is impossible without squeezing. See 302:12. (It forbids using a cloth to clean a cup with water or wine inside, for he will come to squeeze.)

Eliyahu Rabah (19): His first question is not difficult. Even though he is not particular to squeeze the sponge, it is squeezed between his fingers. The Magen Avraham himself (302:27) forbids such a case (using a cloth to clean a cup with water)! To answer the second question, I say that the Gemara discusses a wet sponge (then it is a Pesik Reishei). If one uses a dry sponge to clean something wet, it is not a Pesik Reishei. I defend the text of the Mishnah 'Chachamim say, in either case one may clean.' Tosfos rejected this text, for it is a Pesik Reishei. Do not ask that if so, the Taz should not forbid this, for it is not a Pesik Reishei. I answer that he does not distinguish between types of sponges. He rejects the text I defended. See what I wrote 302:22. The Rambam first brought the law of a sponge, and then the decree not to cover barrels of water. The Tur adopted this expression (of a decree) also regarding a sponge.

Kaf ha'Chayim (93): Elsewhere, Chachamim did not decree lest he come to squeeze when he is not particular about the garment. Here, automatically it is squeezed through cleaning. The Mishnah forbids [even with a dry sponge], lest one clean so much that he will squeeze. The Tur and Shulchan Aruch say that it is a decree, i.e. if the sponge is initially dry.

Eshel Avraham: The Magen Avraham asked that laundering does not apply to a sponge, for it is made for this. Also Dash (extracting) does not apply, for what is squeezed out goes to waste. All the more so laundering does not apply to [using a sponge to clean] oil! The Shulchan Aruch cites the Tur. The Rambam says 'so he not squeeze.' One can explains that there is a handle, so it is possible not to squeeze. The Ra'avad holds that it is impossible. The Tur and Shulchan Aruch connote hold that it is possible without a handle. Why do we decree? Also, the Gemara calls it a Pesik Reishei! The Rambam says 'so he will not squeeze' in the case when there is a handle. Rashi's opinion is not clear. The Drishah says that he refers to when there is no handle. When there is a handle, it is not a Pesik Reishei. I do not understand Eliyahu Rabah, who says that when there is a handle, it is not a Pesik Reishei. Rashi (143b DH u'Bilvad) says that we forbid soaking up wine, lest he squeeze it into a Kli. Tosfos (DH Chavis) says that even if it has a handle, it is forbidden, for this is like one does during the week. The Rambam says that if he does like during the week, he will come to squeeze. The Magid Mishneh connotes that this is like Rashi. Tosfos should have asked that it is a Pesik Reishei! We can say that Rashi forbids oil due to Uvda d'Chol, and wine is a decree lest he squeeze, even if there is a handle, for [afterwards] he wants the wine to leave the sponge. Rashi holds that laundering applies also to wine, but not to oil. One may absorb oil in a sponge, for he holds (Sof 145a) that the Torah Isur of squeezing applies only to grapes and olives, and laundering does not apply. Soaking up is not Uvda d'Chol.

Mishnah Berurah (46): One may not use a sponge to clean a tabletop or bowl.

Gra: 'Decree' in the Shulchan Aruch is a printing mistake. It should say 'due to squeezing.'

Mishnah Berurah (48): Also the Magen Avraham says that this is a mistake, for the Gemara says that without a handle, it is a Pesik Reishei.

Bi'ur Halachah (DH Sefug): Eliyahu Rabah and Tosefes Shabbos lean to be stringent about a dry sponge, for we do not distinguish. Rashi (143a DH Nital) connotes unlike this. In practice, this requires investigation.

Shulchan Aruch (335:1): If a barrel broke, one may soak up, i.e. put a sponge in the wine for it to drip out afterwards. This is a decree lest he squeeze. Even if it has a handle, and there is no concern for squeezing, it is forbidden, for this is Uvda d'Chol.