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Dash: Freezing and Thawing Ice

Rav Yosef Zvi Rimon
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By Rav Yosef Zvi Rimon




Shiur #13: DASH (Part 5)




May one put an ice cube in an empty cup in order to melt it? 

Is it permissible to put ice cubes in a pitcher of juice? 

May one put water in the freezer?


Melting Ice


The Gemara (51b) cites a beraita:


And neither snow nor hail may be crushed on Shabbat to cause their liquid to flow, but they may be placed in a goblet or dish, without concern.


The beraita forbids crushing ice on Shabbat, but allows one to put it into a cup so that it will melt on its own.  Why?


The Rashba (ibid.) explains (the Ramban ibid. and Rambam 21:13 seem to indicate the same) that this prohibition stems from the issue of sechita (squeezing), part of the melakha of dash.  Just as it is forbidden to squeeze a fruit (which is designated for liquid) and turn it into a drink, so too it is forbidden to crush ice and turn it into water:


It appears to me that this was disallowed based on the prohibition of sechita of fruit designated for drinking, because the hail and snow are designated to become water.  Therefore, putting it in a cup is permissible, because one does not appear to be squeezing.


On this approach, one may place ice into a cup (even if it is empty) so that it will melt on its own, because this is not similar to sechita.


However, other Rishonim cite an alternate explanation for this prohibition, unrelated to the melakha of dash; Rashi (ibid. s.v. Kedei) explains that this is forbidden: "because this is molid (“creating” a new entity) on Shabbat, and it is like a melakha, that one creates the water."    


This idea is expressed differently by the Sefer Ha-teruma (Ch.  234-235):


One may not crush snow and make it clear as water, because it is nolad...  If so, it is forbidden to wash one's hands in snow or frozen water... because one dissolves them and turns them into water, so that it is nolad.  It also appears that one may not put a kugel in winter next to the fire in order to warm it up on Shabbat day; since the fat in it has congealed and become thick and opaque, and now it melts and becomes clear, this is nolad.


On this approach, the prohibition is because of the law of nolad, and a similar prohibition exists in putting a food with congealed fat near the fire, since the fat becomes liquid, which is a problem of nolad.  The simple reading of the Sefer Ha-teruma is that crushing ice is prohibited because of nolad. What is nolad? Nolad literally means “born,” and refers to an object that was “created” on Shabbat.  The general problem with such a substance is that it is considered to be muktzeh (since it was not available for use at the beginning of Shabbat).  This is the way the Ramban and Rashba mentioned above understand the view of the Sefer Ha-teruma (and dispute it). 


According to this understanding, the problem with crushing ice does not lie in any action performed, but rather in the result brought about, namely, the water that was “created.”  As such, the prohibition applies even if one puts the ice into an empty vessel without crushing it by hand; since the water is nolad, it makes no difference how this comes about.  Only if one puts the ice in a cup which has a liquid in it does the Gemara allow one to use the water created, since the ice-water is not noticeable, as it is integrated in with the other liquid.


However, on closer examination, it is possible to understand the words of the Sefer Ha-teruma differently.  It may be that when he talks about nolad, he does not refer to the result, namely that the water is nolad. Rather, he categorizes the act of crushing ice as molid, along the lines of Rashi's phrasing.  And indeed the Rosh (4:13) seems to understand that the Sefer Ha-teruma prohibits melting ice because of molid.  According to this, the prohibition is specifically when one crushes by hand; perhaps if one violates this ban and crushes the water, the water would be prohibited to drink as well.[1]  However, if the ice turns into water on its own, there would be no prohibition upon the resulting water.


If the prohibition is specifically the action of holada, why does the Sefer Ha-teruma forbid putting fatty food near the fire?  Does the fat not melt on its own?  From the words of the Sefer Ha-teruma later on, it appears that specifically putting it next to the fire is forbidden, because this is considered to be an action of heating; however, if someone leaves the food out and it thaws on its own, this is mere gerama (causation), and there is no prohibition in this.  So too, it would be allowed, according to him, to put ice in an empty vessel, since the thawing takes place on its own, not by human action.


Summary and Practical Ruling


To conclude, one may not crush ice on Shabbat, because:


1.    Ramban, Rashba, Rambam: It is similar to squeezing produce.  According to this, it is permissible to put ice into an empty vessel, because this is not an action which is comparable to sechita.

2.    Rashi, Rosh (explaining the Sefer Ha-teruma): It is similar to a melakha, because one “creates” the water, thus violating molid.  According to this, one may put ice in an empty vessel, since the water is created on its own, and not through human actions.

3.    Ramban and Rashba (explaining the Sefer Ha-teruma): It violates the prohibition of nolad — a new product being “created” on Shabbat, which is muktzeh.  According to this, the prohibition is applicable to putting ice into an empty vessel as well.


The Shulchan Arukh (318:16) rules against the view of the Sefer Ha-teruma and allows putting a fatty food by the fire in order to thaw it out.


One may put a kugel by the fire in a place where the hand withdraws [due to the heat], even though the fat which is congealed within it melts again.


Similarly, the Shulchan Arukh (320:9) allows one to melt ice:  


One may not crush snow or hail, breaking them into little pieces so that the water will flow from them, but one may put them into a cup of wine or water so that they melt on their own, and one need not be concerned.  Similarly, if one leaves them in the sun or by the fire and they melt, this is permissible.


The language of the Shulchan Arukh ("if one leaves it in the sun...  this is permissible") implies that he allows this only after the fact, but the Mishna Berura (35) writes that the Shulchan Arukh's intent is to allow this in the first place, just as he allows one to put a food with congealed fat in it by the fire. 


On the other hand, the Rema (318:16) writes that the custom is to follow the view of the Sefer Ha-teruma and not to leave a fatty food by the fire, unless there is some great need:


There are those who are stringent, and the custom is to be stringent.  However, in a place of need, one may rely on the former view.     


The Mishna Berura (320:35) writes that according to this, one must be stringent about ice as well, that one may not melt it by the sun or by the fire, but only in a full cup.


According to this view, may one put ice in an empty vessel so that it will melt on its own?  The Acharonim debate this.


Rav Neuwirth writes (Shmirat Shabbat Ke-hilkhata 10:3, n. 7) that just as the Mishna Berura forbids melting ice in the sun, melting ice in an empty vessel at room temperature should also be forbidden.  According to him, the Mishna Berura rules in accordance with the Ramban and Rashba’s explanation of the Sefer Ha-teruma, namely, that the prohibition of crushing the ice is because of nolad, and thus it is prohibited even if the ice melts on its own.


The Shevet Ha-levi (Vol. VII, Ch. 40) writes that the Mishna Berura rules in accordance with the Rosh's interpretation of the Sefer Ha-teruma, that the prohibition exists only in a situation in which there is molid of the water, not in a situation in which the ice melts on its own.[2]  According to him, the Mishna Berura forbids specifically thawing in the sun, which is considered to be leaving it in a heated place, similar to placing it near the fire; however, taking it out of the freezer into room temperature is not forbidden according to him, because this action does not cause the thawing in a direct way, but only removes the cooling agent and allows the thawing to happen on its own.   


The Sephardic practice is to permit removing ice from the freezer, leaving it in an empty vessel so that it will melt.  Similarly, it permits heating food with congealed fat and the like.  For example, Sephardim may heat chicken on Shabbat even if there is a lot of congealed sauce on it.[3]  


On the other hand, Ashkenazic practice is generally to be stringent in accordance with the view of the Sefer Ha-teruma.  As such, Ashkenazim should not put ice cubes in an empty cup, but only in a cup with a liquid in it, as Rav Neuwirth rules.  However, this stringency does not apply when there is a Shabbat-related need, and thus in such cases one may thaw a frozen liquid (e.g., a container of milk[4]).  It is permissible even to leave it near a heat source in order for it to thaw rapidly (on the condition that there is no problem of cooking, i.e., that it is placed in a position where it is impossible for it to reach the temperature at which one withdraws one's hand); this is because, as we noted, the matter is allowed according to most Rishonim, and the Rema rules that one may rely on their view in a time of need.[5]


According to all views, one may not crush ice by hand in order to turn it into water (OC 320:9).  However, one may walk on snow even though one crushes it (ibid. 13), because one has no intent to liquefy it (Mishna Berura, 39), and it is unavoidable (Taz, 10).




Is one allowed to put water in the freezer so that it will turn into ice?


This is apparently a function of the argument of the Rishonim which we have seen: according to the Ramban and the Rashba, it is clear that the matter is permissible, because this is not comparable to squeezing produce (this is the opposite action!), and there is no prohibition of nolad; according to the Sefer Ha-teruma, there is good reason to forbid this because of nolad, since this action causes a new creation of ice.  As such, this would be permissible for Sephardic Jews, while for Ashkenazic Jews, one can allow this only in a time of need.


However, the Dovev Meisharim (Vol. I, Ch. 55) writes that freezing water is forbidden even according to the Ramban and the Rashba.  According to him, these Rishonim rule leniently only about ice which turns into water, since even when it is still ice, if the person thinks to use it for drinking, it is considered a liquid (according to the Gemara in Nidda 17a); consequently, in its melting, a new liquid is not created.  On the other hand, when a person turns the water into ice — which is not being used as a drink right now — one takes something which is defined as a liquid and nullifies the status of liquid, and this act is forbidden because of nolad even according to the Ramban and the Rashba.  According to this, even Sephardic Jews may not freeze water, even in a time of need. 


However, in practice, it appears that freeing water is permissible even for Ashkenazim, at least in a time of need.  First, it is logical that the Ramban and the Rashba dispute the very basis of the Sefer Ha-teruma's view, and they believe that there is no prohibition of nolad unless an entirely new entity is created, not if something merely changes its form.  (Indeed, there are those who understand this in the view of the Sefer Ha-teruma himself, as we have seen above.)  Beyond this, it may be that freezing water is less significant than thawing ice and is allowed even according to the Sefer Ha-teruma, since water's solid state is a temporary situation, not natural for it, and it requires extreme cooling in order to exist.  Simply, it may be that the prohibition of nolad is not applicable to something which does not last.     


Practically, it appears that one may be lenient about this, at least when there is a need for Shabbat.  Many halakhic authorities of the recent generation rule accordingly, among them the Shevet Ha-levi (Vol. III, Ch. 55), Rav S.Z. Auerbach (Shemirat Shabbat Ke-hilkhatah, Ch. 10, n. 14), the Tzitz Eliezer (Vol. VI, Ch. 34; Vol. VIII, Ch. 12), the Chelkat Yaakov (OC, Ch. 128-129) and the Minchat Yitzchak (Vol. VIII, Ch. 24).[6]




To conclude, one may not crush ice on Shabbat, but it is permissible to walk on snow.  Sephardim can put ice or fat in a bowl so that it will melt (or heat it up in one of the permitted ways), and so too, they are allowed to freeze water in order to create ice.  Ashkenazim are accustomed not to put ice cubes in an empty cup, but only in a vessel which contains a liquid; similarly, their custom is to prepare ice before Shabbat and not on Shabbat itself.  However, when there is a need for Shabbat itself, Ashkenazim can also put ice in an empty vessel or thaw a milk container and the like, and they may also freeze water in order to create ice.

Translated by Rav Yoseif Bloch

[1] From the abovementioned view of the Rosh, also found in the Or Zarua (Vol. II, Ch. 62), it appears that the prohibition is only on the action of holada, and in any case the water which is nolad is not forbidden, while according to the Magen Avraham (318:42), if one crushes ice in a forbidden way, the liquid created is forbidden.

[2] According to the Shevet Ha-levi, the rulings of the Magen Avraham (318:42) and the Mishna Berura (ibid. 106) prove that one is allowed to put fatty food in an oven which is off so that a non-Jew will turn on the oven, since the Jew does not cause the melting directly; the Jew puts the fat down, and it is the non-Jew who is the cause of the melting at a later point.  Presumably Rav Neuwirth would explain this away by claiming that putting food into an oven which is shut off is not a significant act as long as the non-Jew does not turn the oven on (the fat will not melt if the oven remains off), and therefore it is possible to allow it.  However, removing the ice from the freezer and putting it an empty vessel starts the process of defrosting immediately, similar to putting it in the sun, and therefore it should be prohibited.

[3] This allowance applies provided that there is no problem of cooking.  We deal at length with both the prohibition of cooking, and the ban of nolad, as they apply to congealed sauce, in our shiurim on those topics.

[4] When it comes to milk, there is another reason to allow it, namely that milk is only used as a drink, and thus even when it is frozen it has the status of a mashkeh (liquid), in which case melting it is not molid of a mashkeh.  Ice, on the other hand, does have the status of mashkeh as long as one does not explicitly think about using it for drinking (as explained in the Gemara, Nidda 17a, concerning snow), so that melting it creates a new mashkeh (Rav S.Z. Auerbach, cited in Shemirat Shabbat Ke-hilkhatah, Ch. 10, n. 15).

[5] In fact, even if one melts ice in a normal situation — i.e., not a situation of great need — one is allowed to drink the water, because the Mishna Berura (318:107) rules that after the fact one may rely on the lenient view here.  However, Rav S.Z. Auerbach (Shemirat Shabbat Ke-hilkhatah, Ch. 10, n. 10) writes that the Mishna Berura is only lenient when it comes to heating up sauce with congealed fat, but when it comes to defrosting ice, because there is no great need to drink specifically this water as opposed to any other liquid, one who has other drinking water should not drink the water produced from the melted ice.

[6] However, Rav J.B. Soloveitchik rules that in freezing water, when one turns a liquid into a solid, one must be concerned about a Torah prohibition of building (Mi-peninei Ha-Rav, p. 79).


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