Liquid soap and eye cleanser on Shabbat - Matan - The Sadie Rennert

Liquid soap and eye cleanser on Shabbat Rabbanit Chanital Ofan

June 2021

Topic : Shabbat & Yom Tov ,


1) Can all liquid soap be used on Shabbat? Some “al sabon” is more like a gel.

2) I have a foam eye wash that I use twice a day. When pressing the pump, the liquid turns into foam. Can that be used on Shabbat?

Thank you very much.


Using Foaming Soap to Cleanse Eyes on Shabbat

The debate regarding the use of foaming soap to cleanse eyes on Shabbat involves three separate issues:

·         Cleaning the eyes, and the rabbinic prohibition to take medication on Shabbat because it might lead to grinding herbs (שחיקת סממנים).

·         The prohibition of smoothing a surface on Shabbat (ממחק) and of creating a new entity (נולד) by diluting a thick liquid solution on Shabbat.

·         The prohibition of building (בונה) which includes acts of creation such as turning liquid solution into foam.

Healing the Eyes on Shabbat

The Talmud (Shabbat 111a) states that it is prohibited to swallow vinegar on Shabbat to relieve tooth pain, since this might lead to grinding herbs (שחיקת סממנים). The Rosh (end of sec. 8) and the Ran (Rif on Shabbat 39b, end of s.v. ומהא) argue about a case of severe pain. According to the Rosh, severe tooth pain puts one in the category of a person who is sick but without risk (of loss of life – חולה שאין בו סכנה), in which case one is permitted to transgress a rabbinic prohibition. Conversely, the Ran prohibits medication in this instance based on the explicit Talmudic reference to tooth pain, which is clearly severe, and nonetheless prohibited. The Shulhan Arukh (Orah Haim 328:1) ruled according to the Ran, and prohibited medication as long as one is not bedridden due to the pain.

However, eye disease is regarded differently. According to Rav Yehuda (Avodah Zarah 28a) the eyes are connected with the heart; therefore an eye infection is more severe than the category of losing a limb, and is in fact considered a case of the preservation of human life (פיקוח נפש). However, when it is clear that the ailment is minor, rabbinic law prohibits treating the eyes on Shabbat as well. Therefore, the Talmud (Shabbat 108b) prohibits dripping wine into one’s eye, since this is considered a form of medication; however, it permitted to dab wine on one’s eyelids, to cleanse them. This is also the ruling of the Shulhan Arukh (Orah Haim 328:20). Moreover, preventative medical treatment was also permitted on Shabbat; therefore, one may cover the eye with a medicated bandage on Shabbat (ibid. 28) and sterilize wounds with wine (ibid. 29).

According to this, eye treatment is permitted in two extreme situations: either a dangerous infection, or a hygienic preventative measure that would also be applied by a healthy person – even when the purpose of the treatment is ultimately to heal, but the medical treatment is used to prevent a deterioration of the condition.

The current question refers to cleansing the eyes; therefore, even if the reason for cleaning the eye is an infection, this is permitted; all the more so given that healthy people use soap for cleaning.

The Prohibition of Creating a New Entity (נולד)

The Rema (on Shulhan Arukh, Orah Haim 326:10) rules against washing one’s hands with salt grains and water on Shabbat, and all the more so with soap or animal fat (chelev), since these “dissolve into his hands, and by this he creates a new entity.”

The concept of נולד – creating a new entity – is mentioned by Rashi (on Shabbat 51b) regarding crushing snow or hail by hand in order to turn them into liquid. Rashi categorizes this action as מוליד since he considers the act of changing form as creating something new. Sefer Hateruma (235) and the Ran (on the Rif 23b s.v. ואין) debated the status of this prohibition: Sefer Hateruma views נולד as an independent prohibition, while the Ran views it as an injunction due to the concern that one might end up transgressing the prohibition of wringing or squeezing (סוחט). The practical ramifications of this disagreement relates to the result of melting or dissolving that occurs on its own; Sefer Hateruma prohibits even melting animal fat in the sun, while according to the Ran only directly melting by hand is prohibited. The Rambam (Shabbat 21:13) seems to rule according to the Ran’s position[1].

In a similar context, the Shulhan Arukh (Orah Haim 318:16) allows the placement of a cooked dish containing fat near the fire, knowing that the congealed fat will inevitably become liquid. The Rema (in the name of R. Yeruham) adds that this is permitted even when the fat is clearly separate from the food; however, he notes that “there are those who prohibit due to נולד” (referencing the Ran).

Indeed, the Mishnah Berurah (105) and Arukh Hashulhan (32) both adopt this distinction: in the case of melting snow or ice into a cup of water, the result of נולד is independently discernable. Conversely, when food sits in a sauce, there is no clear separation between the food and the liquid that comprises a ‘new creation.’ The Rema rules that in the first case one should be stringent, and attests that this is the prevalent custom; however, when there is a great need, he notes that the lenient position may be relied upon.

Regardless, the prohibition is defined as turning a solid – whether soft or hard – into liquid, not by means of cooking. However, in the case before us, the question was posed regarding liquid (foam) soap. In this case, the dilution does not affect the state of aggregation, and there is therefore no concern that its use will create a new entity. The Mishnah Berurah (326:30) rules that one may wash one’s hands with salt water that was prepared in advance (and cites the Magen Avraham who states that solids that are not usually used in liquid form, or liquids that are not recognized as an independent entity, such as fat or soap, are never in the category of the prohibition of נולד).

Smoothing a Surface on Shabbat (ממחק)

However, the Mishnah Berurah (326:30) cites the Tiferet Yisrael, who prohibits the use of bar soap due to ממחק – smoothing a rough surface on Shabbat, since the regular use of the soap smooths the bar of soap. He nonetheless permits the use of soap if it was soaked in water before Shabbat, creating a soft mixture.

One of the derivatives of the prohibition of ממחק is another prohibition of ממרח – smoothing by spreading a substance over a surface (instead of smoothing by eliminating surface). One example of this prohibition is mentioned in the Mishnah (Shabbat 22:3) that states the prohibition to seal a barrel with wax due to ממרח. 

Contrary to the Mishnah Berurah, R. Moshe Feinstein (Orah Haim 113) believed the soap should be entirely liquid due to the concern of ממחק – smoothing by spreading a substance. However, the majority of halakhic authorities (including among others Arukh Hashulhan ibid.; Tzitz Eliezer vol. VI 34; R. Shlomo Zalman Auerbach, Shemirat Shabbat Kehilkhata[2] 14:49; Yabia Omer 4:27) are not concerned with ממרח in the case of liquid soap, as long as it is not a solid. The debate regarding liquid baffled Ahronim.

Indeed, the categorization of soap under the prohibition of ממרח seems odd, since the Rambam (11:6) and the Shulhan Arukh (328:26) imply that this prohibition involves smoothing the external layer of an object, while soap is independently smooth, and the act of using soap involves eliminating a layer for use, but in the process there is no change in the smoothness of the soap. Accordingly, R. Ovadia Yosef mentions in various responsa that many halakhic authorities (Resp. Ginat Veradim, Pahad Yitzkah, and others) permitted the use of regular bar soap, and he tends to rule accordingly. However, in practice R. Ovadia (Yabia Omer, Orah Haim 4:27) testifies that this is not prevalent practice, and adds that the Ashkenazi community should be stringent in this matter (Yoreh Deah II 50).[3]

Accordingly, the use of gel soap should not be categorized as ממרח according to the majority of halakhic positions.

Foaming Soap

Creating foam out of soap is a change in the state of aggregation, from gel to thick foam. This raises the question whether the foaming of soap should be categorizes under the prohibition of building (בונה). The Tzitz Eliezer (vol. VI 34) discusses freezing water and making ice cream on Shabbat, based on the baraita (Shabbat 95a) that prohibits making cheese on Shabbat because of בונה – creation. He cites the Ben Ish Hai (Shana Shniya, 19; Shana Rishona, Bemidbar 10) and Shevitat Hashabbat (I 4-5:2) who prohibit these actions.

However, the comparison between making cheese and freezing is not obvious, since ice cream and ice do not maintain their frozen form outside the freezer, as opposed to cheese, which can never return to its liquid form.

The Babylonian Talmud (Shabbat 31b) and the Yerushalmi (7:2) disagree on whether a temporary creation is prohibited on Shabbat, or conversely, is not considered a creation at all. According to some Rishonim the Babylonian Talmud permits a temporary creation, while the Jerusalem Talmud prohibits such an action on Shabbat. As a proof, the Yerushalmi (12:1) brings the building of the Tabernacle, which was clearly temporary, and prohibited on Shabbat; however, R. Yossi there raises a similar argument to the process outlined in the Babylonian Talmud, which concludes that since the Tabernacle was constructed by divine command, it took on the status of a permanent structure. The Hatam Sopher (Orah Haim 72) rules according to the Babylonian Talmud, and like the Yerushalmi in ch. 12, and permits creating an impermanent construction.

Tzitz Eliezer debates whether freezing water on Shabbat should be considered creation (בונה), but permits based on the argument above. Conversely, R. Shlomo Zalman Auerbach prohibits freezing water on Shabbat (Shemirat Shabbat Kehilkhata 10:4 no. 14) because of נולד – creating a new entity, and only permits when there is an acute need. However, he does permit defrosting when the change only affects the texture and not the essence of the product; for example, ice cream is considered edible even when defrosted, and is therefore not prohibited when melted due to נולד (10:7-8, no. 20).

An interesting discussion revolves around creating soap bubbles while washing dishes, since the bubbles are impermanent, and their creation is inadvertent. For these reasons, R. Shlomo Zalman Auerbach does not categorize bubbles as נולד (Shemirat Shabbat Kehilkhata 16:30, and notes 80-81). However, with regard to blowing bubbles for play, he prohibits their creation by adults despite their impermanence, but allows children to blow bubbles. This distinction attests that there is no essential prohibition in blowing bubbles on Shabbat. There is no question that the status of bubbles is even less severe than freezing, since they are extremely impermanent; accordingly, R. Lior permits adults to blow bubbles on Shabbat as well, reasoning that they are temporary.

With regard to the question above, since creating the foam is not an independent goal, and the foam is only meant to make the product easier to use, we may infer that there is room to permit washing one’s eyes on Shabbat, which can be considered a dire need, perhaps even according to the position of R. Shlomo Zalman Auerbach.


As explained in detail above, according to most halakhic authorities there is no reason to prohibit using foaming gel soap to wash one’s eyes on Shabbat.

Shabbat Shalom and Wishing you good health!


[1] According to the Rambam’s formulation, this is a derivative of wringing (סוחט), and the Maggid Mishneh on the Rambam and Shiltei Giborim on the Rif (23b, 6) offer a similar explanation.

[2]All references to Shemirat Shabbat Kehilkhata are from the second edition, 1979.

[3] R. Kappah (in his commentary on the Rambam, Shabbat 21:3) argues that according to the Rambam there is no creation of a new entity (נולד) in the case of liquefying snow, and therefore he permits the use of soap on Shabbat: “therefore it is certain;y permitted, according to our Rabbi, to use soap on Shabbat, both because soap today is hard and cannot be wrung, and because the prohibition of נולד does not apply to soap on Shabbat … this was the prevalent custom in Yemen for generations, to wash the entire body with soap.”

Rabbanit Chanital Ofan graduated from Matan’s  Advanced Talmudic Institute.  She has an M.A. in Talmud from Bar Ilan University and is a Certified Halakhic Advisor (Yoetzet Halakha) by Nishmat.  For the last 18 years she has taught Talmud and Midrash in a number of women’s Batei Midrash. She is in the first cohort of Hilkhata Matan’s Advanced Halakha Institute and a lecturer in Matan’s Metivta program.

A few words about the project שאלה - כתובת נשית לשאלות בכל תחומי ההלכה. מי המשיבות שלנו? בוגרות תכנית הלכתא - תכנית שש שנתית ללימודי הלכה במתן. לכל המשיבות רקע עשיר בלימוד גמרא והלכה והן משמשות כתובת לשאלות ופניות בקהילה ובבית המדרש. כל התשובות נידונות בקרב הוועדה ההלכתית של 'שאלה' בה, יחד עם המשיבות, יושבים הרב הדיין אריאל הולנד והרב יהושע מאירסון.

Support Shayla