Lash: Lisha Achar Lisha
THE LAWS OF SHABBAT
By Rav Yosef Zvi Rimon
Lash, Part V
IX) Lisha Achar Lisha
Is one allowed to prepare tahini or dilute it on Shabbat? Is there any problem of lisha in adding oil to a salad made of finely-chopped pieces?
The halakhic consensus is that in the melakha of cooking, ein bishul achar bishul (literally, there is no cooking after cooking). Do we also rule that ein lisha achar lisha (there is no kneading after kneading), i.e., once a substance has undergone lisha, any additional kneading, mixing, stirring, whipping, beating, etc. is meaningless; or do we say that one violates the prohibition of lisha again?
Kneading Mustard-Seed in the Gemara
The Bei’ur Halakha (321:15, s.v. Yakhol Le’arvo) writes that indeed ein lisha achar lisha, and he cites the following passage from the Gemara (140a) to prove this:
If mustard is kneaded on Erev Shabbat, the next day one may mash it either by hand or with a utensil, and one may pour honey into it. One may not beat it, but one may mix it…
According to the Bei’ur Halakha, the Gemara is talking about mustard-seed which has been mixed with a liquid and kneaded on Erev Shabbat. The Gemara allows one, on Shabbat, to add a liquid to the mixture in order to dilute and soften it or to add honey to it, as long as one mixes gently and not vigorously.
According the Rif (58a), the Rambam (22:12) and most Rishonim, the Gemara deals with mustard which was crushed before Shabbat but not mixed with liquid or kneaded; nevertheless, the Gemara allows one to mix liquid in it on Shabbat and knead it, as long as one mixes gently and not vigorously. The phrasing in the Gemara, “If mustard is kneaded”, refers not to the melakha of lisha itself, but rather to mustard that is “kneaded” with its natural juice (Peri Megadim, Mishbetzot Zahav, 319:13).
The Sefer Ha-teruma (Ch. 220) disputes this and understands that case as referring to a situation in which one puts in water before Shabbat but does not mix the mustard-seed and the water. The Terumat Ha-deshen (Ch. 53) explains that the Sefer Ha-teruma rules like Rabbi, and therefore he holds that in any case one may not allow putting in liquid on Shabbat, and the fact that one changes the method of mixing does not make adding liquid permissible, so that we have no choice but to say that the Gemara is talking about a case in which the liquid was put in before Shabbat.
However, the Bei’ur Halakha finds the approach of these Rishonim very difficult:
In truth, this requires a great deal of study: how did the Sages allow the very kneading, which is a Torah prohibition, on the basis of such as small shinnui, namely that one does not beat it vigorously?
In other words, given that kneading this mixture ordinarily would involve a Torah prohibition, how could it be that the Sages allowed it in the first place, even with a shinnui? Therefore, the Bei’ur Halakha suggests a third explanation (which he understands as the view of the Rambam as well): we are talking about mustard-seed to which a) a liquid was added, after which b) the mixture was kneaded on Erev Shabbat, as is the simple meaning of the Gemara’s phrasing. Therefore one is allowed to knead the mixture once again on Shabbat, because ein lisha achar lisha; nevertheless, there is a rabbinic prohibition to beat it vigorously, because this action is similar to lisha.
The Bei’ur Halakha explains the logic behind this:
The mustard has been kneaded while it was still day… Therefore, in mashing it now on Shabbat, one is not doing an act of lisha at all… This mashing of the mustard merely makes it very soft, so that it can be drunk, and this act is not called lisha… Thus, mashing in water is the opposite, as one separates the parts which adhere through lisha. Consequently, there is no prohibition in this at all, except that beating it vigorously is a bit similar to lisha.
That is to say, the nature of the lisha is the binding of substances together. When the mass is kneaded before Shabbat, the parts are already fused, and another act of mixing does not connect them together any more. In fact, the adding of water is not forbidden because of lash because the water makes the mass more liquid and more separate — the reverse of the melakha of lash, which seeks to create attachment and adhesion. (The only issue is that if one mixes vigorously, the act is rabbinically prohibited, because it resembles lisha).
We should note that the Bei’ur Halakha’s approach is very innovative and is against the simple understanding of the Rishonim cited. (As for his question about permitting a Torah prohibition if one merely does the act casually, we will raise the possibility below that this allowance is limited to pulped produce only, which does not adhere after lisha.) In any case, even though this interpretation is innovative, the basic principle which emerges from his words, that ein lisha achar lisha, is a matter of general agreement among the halakhic authorities. One should point out that even though the Bei’ur Halakha’s words indicate that the principle of ein lisha achar lisha applies only when one mixes gently, other halakhic authorities do not require this, and even he does not mention this requirement in his Mishna Berura. (From a logical point of view, it is not obvious that one must mix it gently in a situation in which there is no prohibition of lisha at all.) This issue will be addressed further with regard to lisha of pulped fruits and vegetables.
Applying Ein Lisha Achar Lisha
The principle of ein lisha achar lisha is cited by additional halakhic authorities (Taz, 321:13, based on the Terumat Ha-deshen, Ch. 53; Chazon Ish, 58:5, et al.) and it is similar to the principle we mentioned initially, ein bishul achar bishul.
As we have said, in addition to the allowance to knead an existing mass, one can add liquids to it or dilute it, because this is the opposite act of the melakha of lash. However, one must not add dry substances to the mass, even if the mass was formed before Shabbat, because one is binding dry substances to this mass on Shabbat, and this is an act of lisha. Therefore, it is clear that one must not, for example, add flour to existing dough.
According to this, it is permissible to mix on Shabbat tahini which was prepared before Shabbat, and one is allowed to add water to it. Similarly, one is allowed to mix the oil on top of a jar of peanut butter with the contents below. One may also mix the oil which floats on top of eggplant salad back into the mixture.
What about charoset, the paste made for the Pesach Seder? As long as it has been initially prepared before the holiday starts, one is allowed to add wine or another liquid (even when the Seder takes place on Friday night).
However, it is appropriate to avoid preparing unprocessed tahini on Shabbat. Though it has already been mixed during its processing in the factory long before this Shabbat, it has only been “kneaded” with its natural juices, and it is not clear that this is considered true lisha. In addition, the preparation of tahini improves the mixture and makes it thicker. However, some authorities are lenient and allow preparing tahini on Shabbat. In any case, one is allowed to mix more thoroughly the raw tahini itself with the oil floating on it.
If the Second Lisha Enhances
When it comes to ein lisha achar lisha, we must ask: from an essential point of view, is it conceivable for there to be a prohibition of lisha once lisha has already been done? Perhaps ein lisha achar lisha applies only because there is no enhancement or innovation in the second lisha, but if there is any enhancement, it would be forbidden. A practical distinction will arise between these possibilities within the view of Rabbi, who believes that for putting water in one is liable for lash: can one be liable for the kneading as well, or perhaps after the water is put in and lisha has been accomplished, ein lisha achar lisha?
As we have seen above, according to the Bei’ur Halakha (321:14, s.v. Ein Megabbelin), even if the water has been put in on Erev Shabbat and only the kneading is done on Shabbat, one is liable even according to the view of Rabbi, and we do not say that this is lisha achar lisha, since the kneading improves the dough and makes the two substances better adhere to each other. The Bei’ur Halakha brings a proof from the Yerushalmi (7:2), which says that even one who rolls dough is liable, despite the fact that the dough has already been kneaded. This implies that one is liable even for improving existing dough. On the other hand, the Chazon Ish (58:5) writes that, according to Rabbi, one is not liable for kneading because ein lisha achar lisha, and one cannot bring a proof from the Yerushalmi, because rolling is a separate act from kneading.
It turns out that according to the Bei’ur Halakha, the entire rule of ein lisha achar lisha is only applicable when the second lisha adds nothing significant; however, if the second lisha enhances the mixture, one is liable for it. (According to him, it may be that the same applies even if one actually kneads before Shabbat — if the second lisha improves the attachment of the substances in the mass in a significant way, one is liable for it.) On the other hand, according to the Chazon Ish, we rule categorically that ein lisha achar lisha, and only for totally new actions (e.g., rolling) may one be liable after lisha.
In conclusion, the general principle is that ein lisha achar lisha. Therefore, if one mixes a solid with a liquid and kneads them before Shabbat, it is permissible to knead them more thoroughly on Shabbat. In this case, one can even add water and knead, since this act does not make the mass more cohesive; on the contrary, this act separates it. (Still, one cannot add dry substances to an agglomerated mass and knead the mixture). Therefore, it is permissible and to mix tahini which was prepared before Shabbat (though it is inappropriate to prepare unprocessed tahini on Shabbat) or to mix the oil which floats on top of peanut butter with the rest and the like.
X) Lisha of Pulped Produce
The regular lisha is that of flour and water or other substances with liquids and the like. Does the prohibition of lash apply when one adds liquid to pulped vegetables? Is there a problem to add wine on Shabbat to crushed walnuts and apples which are designated for charoset? Can one add oil to a finely-chopped salad?
The Gemara (140a) states:
If mustard is kneaded on Erev Shabbat, the next day one may mash it either by hand or with a utensil, and one may pour honey into it. One may not beat it, but one may mix it.
Cress which has been ground on Erev Shabbat, the next day one may put oil and vinegar into it… One may not beat it, but one may mix it.
Garlic which has been pressed on Erev Shabbat, the next day one may put beans or grits in it. One may not grind it, but one may mix it.
Rashi explains: “‘One may not beat it’ — as one beats eggs in a bowl with a spoon, in the way of beating, that one strikes it vigorously.” The Gemara allows one to mix pulped vegetables with liquids or beans and grits with pressed garlic, as long as one mixes gently and not vigorously. As cited above, the Bei’ur Halakha (321:15, s.v. Yakhol le’arvo) is very perplexed by this allowance:
In truth, this requires a great deal of study: how did the Sages allow the very kneading, which is a Torah prohibition, on the basis of such as small shinnui, namely that one does not beat it vigorously?
It may be that the answer is that generally one cannot allow lisha with a shinnui (alteration) such as this, however in the cases mentioned in the Gemara, there is no problem of lisha, or at least there is no prohibition of lisha from the Torah. The prohibition of lisha is fusing and binding substances. Pulped vegetables that are mixed with liquids do not turn into one unit, and thus the act of mixing them cannot be considered lisha; as such, one is allowed to mix it gently.
The Chazon Ish (58:4) explains why this is permitted along similar lines:
It is possible that even if one beats it vigorously, it is only [prohibited] rabbinically, and even if we say that beating it vigorously is [prohibited by] Torah [law], one must say that mixing it is not a full-fledged violation of lash. This is not based on shinnui: it is less cohesive than ashes, as they become like miry clay when mixed with water… but minced vegetables are not miry, but discrete. However, when one beats them vigorously, it may be considered lisha by Torah law.
The Chazon Ish deliberated here between two possible understandings. According to the first possibility, vigorously beating pulped vegetables is forbidden only rabbinically, since it does not create a true mass, and therefore when one makes a shinnui one can allow it to be mixed gently. On the other hand, according to the second possibility, beating pulped vegetables vigorously creates a true mass, and the act is forbidden by the Torah. However, mixing vegetables like these gently does not create an agglomerated mass at all, as the vegetables remain separate, and therefore the matter is permissible. (According to this view, the allowance to mix gently is not based on the law of shinnui, and lisha is not at all applicable to a mixture such as this.)
Either way, the allowance to gently mix pulped vegetables with a liquid is based on the fact that one does not create a new single entity, and therefore there is no true lisha in this case.
However, there are Rishonim who limit this allowance in a significant way.
The Sefer Ha-teruma (Ch. 220) writes that according to the Yerushalmi (7:2), that the allowance to knead pulped vegetables gently only applies if one puts in the water before Shabbat, but on Shabbat itself there is no allowance to add a liquid to pulped vegetables. The Semag also mentions this limitation (Prohibition 65, Lash).
In his Responsa (Ch. 53), the Terumat Ha-deshen explains that this view is based on the view of Rabbi, that putting in water is forbidden by the Torah because of lash, and the shinnui done with kneading does not help to permit putting in the water (unless one makes a belila rakka and mixes the substances in the reverse order, as we have explained in earlier shiurim).
As such, according to the Rif, the Rambam and the Rosh, who rule in accordance with the view of Rabbi Yosei bar Yehuda, there is no need to limit the words of the Gemara, and it is permissible to add liquids to pulped vegetables and to knead them gently on Shabbat itself. This is what the Yere’im (Ch. 274, 134a) and the Or Zarua (Vol. II, Ch. 61) write: the Gemara’s allowance applies even to adding liquids to pulped vegetables on Shabbat itself.
Halakhically, the Shulchan Arukh (321:15-16) cites both views:
If mustard is kneaded on Erev Shabbat, the next day one may mash it either by hand or with a utensil, and one may pour honey into it. One may not beat it vigorously, but one may mix it bit by bit.
Cress which has been ground on Erev Shabbat, the next day one may put oil and vinegar into it. One may not beat it, but one may mix it. Garlic which has been pressed on Erev Shabbat, the next day one may put beans or grits in it. One may not grind it, but one may mix it…
There are those who say that it is only permissible to mix a liquid in mustard if it has been put in before Shabbat, but on Shabbat, it is forbidden to put liquids in crushed mustard or garlic because of lash.
Gloss [of the Rema]: If one puts in the food first and afterwards the vinegar or wine and mixes it with one’s finger, it is permissible, because it is a shinnui, just as by shatita above. This is the custom: to allow this with a shinnui.
The Shulchan Arukh first quotes the view of most Rishonim, who allow one to put a liquid into vegetables and to mix it gently on Shabbat — following the view of Rabbi Yosei bar Yehuda — and after this, he cites the view of the Sefer Ha-teruma and the Semag as the second view (“those who say”). They limit the allowance to a case in which one puts in the liquid before Shabbat, following the view of Rabbi. Since he brings the lenient view without attribution and then the stringent view of “those who say,” it appears that his essential inclination is to be lenient. We have already seen that this is the view of the Sefardic halakhic authorities — to rule in accordance with the view of Rabbi Yosei bar Yehuda.
From the words of the Rema, on the other hand, it appears that he is concerned about the view of “those who say”, who follow Rabbi’s view, and he does not allow mixing pulped vegetables unless one puts the liquid in on Erev Shabbat. We have already seen that a number of the Sefardic halakhic authorities also follow this approach, including the Ben Ish Chai and the Kaf Ha-chayim. However, the Rema notes that, even according to the stringent view, one may put the liquid in on Shabbat itself if one makes a belila rakka and changes the sequence of ingredients, as we have seen in our discussion of lisha with a shinnui.
It turns out that according to the mainstream view of the Sefardim, one may add a liquid to pulped vegetables and mix them gently on Shabbat, even though it creates a belila ava, while according to the Ashkenazim (and some of the Sefardim) one should not add a liquid to pulped vegetables and make a belila ava on Shabbat; rather one should add the liquid before Shabbat and mix it gently on Shabbat (or make a belila rakka with a shinnui in the ingredient sequence). Indeed, as we have already seen, if one could not have added the liquid before Shabbat (for example, the food would have gone bad or one had forgotten to do so), one may be lenient in accordance with the view of Rabbi Yosei bar Yehuda and add the liquid on Shabbat itself. In this case, one must mix with a shinnui or gently, and it is best to change the sequence of ingredients as well.
In fact, these laws relate to every belila ava, not only pulped vegetables; however, pulped vegetables have an added leniency of mixing gently (i.e., one mixes it normally — not vigorously, but rather with a slow, circular motion). Generally, this shinnui is not considered sufficient, with the requirement being either to whip it crosswise, to shake the vessel or to mix it bit-by-bit. However, one may be lenient and mix pulped vegetables normally and gently, since the Gemara explicitly states that this is permitted for them (see Chazon Ish 58:8, s.v. Ke-shekkoteshin).
Lisha of Chopped Vegetables
Are these rules applicable only to pulped vegetables, or do they apply to chopped vegetables as well?
The Mishna Berura (321:68) writes, based on the Taz (321:12,) that in this respect, one must distinguish between two levels of chopping:
When it comes to lettuce, one need not be concerned about this, since it is never minced; however, when we mince a radish or pickled cucumbers, pour on vinegar or another liquid and then mix it all together, one must be careful not to mix it vigorously with a spoon, or to shake it in the vessel itself. Preferably, one should be stringent and put the vinegar in the vessel first and then the food.
According to him, if vegetables are chopped up very finely, so that mixing the liquid in causes them to adhere, one must treat them as stringently as pulped vegetables, and therefore one should not add liquid on Shabbat itself. If it is impossible to prepare it on Erev Shabbat, one may add the liquid on Shabbat and mix it gently, but it is preferable to change the sequence of ingredients. However, if the pieces are somewhat larger, and they do not form one mass, there is no problem of lisha at all.
According to this, there is no problem to add liquid to a vegetable salad or fruit salad and to mix it normally, because the contents of the salad are not chopped very finely. (Even if they are chopped in such a way as to create a problem of tochen, they still do not adhere in the presence of a liquid). Similarly, it is permissible to add dressing to a lettuce salad and mix it up, and one may add mayonnaise to small pieces of potatoes (since they are not cut very finely) and mix them normally. One may also be lenient about carrot salad and add orange juice and the like, because there is no real cohesion of different parts. (Still, the salad may at times be cut very finely, and it is appropriate to mix it gently).
Similarly, it is permissible to add cream to chopped strawberries. If the strawberries are pulped, and by putting in a bit of cream, one causes them to adhere, one should mix gently. However, if one puts a lot of cream in, the strawberries do not adhere and merely give a taste to the cream; consequently, one is able to mix it normally.
Similarly, it is permissible to mix leaves of spices in cheese or hummus, because this does not create an agglomerated mass (the leaves scatter and do not adhere to each other), but merely imparts taste.
Translated by Rav Yoseif Bloch
 The Terumat Ha-deshen implies that, according to the view of Rabbi, if one puts in water before Shabbat, there is no Torah prohibition to knead the mixture on Shabbat (according to the view of the Chazon Ish mentioned at the end of the previous shiur), and therefore it is permissible to knead with a shinnui. The Taz derives from this that even if one puts in only a small amount of water before Shabbat, this suffices to render the dough “kneaded”, so that on Shabbat one may add water and knead with a shinnui (as long as one has not added mere drops before Shabbat, but rather a significant quantity of water).
 The Menuchat Ahava (Vol. II, 9:17) allows preparing unprocessed tahini, since it has already been mixed in the factory. However, as we have said, the matter is not simple, and Rav Neuwirth (Shemirat Shabbat Ke-hilkhata 8:26) forbids it. It may be that there is more of a reason to be lenient if one mixes it gently and prepares it proximate to the meal, and this is what the Menuchat Ahava writes there. However, it is better not to rely on this leniency, which is problematic, but rather to prepare the tahini before Shabbat.
 As we saw above, there is no problem with adding wine to charoset prepared before the holiday began.
 As we saw above, the Bei’ur Halakha himself answers that the Gemara talks about which have been kneaded on Erev Shabbat; thus, it is permissible to knead them on Shabbat, because ein lisha achar lisha. Even though the Gemara specifically speaks about mustard, the Bei’ur Halakha understands that even concerning cress, garlic and the like, the case is similar. However, as we have said above, the Bei’ur Halakha’s approach does not accord with the words of the Rishonim, and the Chazon Ish challenges him (58:8, s.v. Ma she-katav ba-Mishna Berura). One should note that the Piskei ha-Rid (ibid.) distinguishes between mustard on one hand and cress and garlic on the other: specifically concerning mustard the Gemara says that one must knead it on Erev Shabbat, since there is no allowance to knead it on Shabbat even gently, as “its lisha is significant”, while cress and garlic may be mixed on Shabbat gently, even if they have not been kneaded on Erev Shabbat. According to our approach, one may say that lisha of mustard creates one agglomerated mass more so than lisha of cress and garlic.
It should also be pointed out that the Or Zarua (Vol. II, Ch. 61) and others explain the words of the Gemara “One may not beat them, but one may mix them” in a very different way from Rashi; they understood that the allowance is to mix with one’s finger and not with a utensil. This is a significant shinnui, and thus one should not be surprised that it suffices to permit an act of kneading otherwise forbidden by Torah law, as we discussed above.
 It may be that there is yet another reason to be lenient about lisha of pulped vegetables. According to the view of the Bei’ur Halakha (321:14, s.v. Shema Yavo) which we will see later on, there is no prohibition of lisha from the Torah for something which is fit to eat as it is. The essence of the melakha of lisha is the preparation of food for cooking and baking; however the lisha of something which is edible as is may be considered mere food preparation (tikkun okhel). However, it may be that there is still a rabbinic prohibition in such a case, and therefore one must also enlist the reason that vegetables do not become one unit.
 If one adds to the mixture items other than vegetables, such as bread crumbs and the like, one should mix with the customary shinnui of crosswise motion.
 See the Shevitat ha-Shabbat (Introduction to the Melakha of Lash, 20) who finds this ruling to be difficult.