The Geder of Davar Lach versus Davar Yaveish: May one reheat a wet and moist food on Shabbos-How wet is considered wet?
*Important note: This article does not deal with the subject of reheating congealed gravy, or foods with congealed gravy, on Shabbos. Melting congealed gravy on Shabbos contains both leniencies and stringencies that are not applicable to reheating regular liquids, and is beyond the scope of this article to delve into. Hence, in all cases that liquid is mentioned below, it refers specifically to actual liquid, or non-congealed gravy, and not to congealed gravy, which will have its own separate article to clarify its law.
It is forbidden for one to reheat a cold liquid on Shabbos even if the liquid was fully cooked before Shabbos. According to some opinions, doing so contains a Biblical cooking prohibition if one heats the liquid to Yad Soledes. This concept is known as “Yeish Bishul Acher Bishul Bedavar Lach.” This is in contrast to a solid food which may be reheated on Shabbos, in certain permitted ways. This concept is known as “Eiyn Bishul Acher Bishul Bedavar Yaveish.” Now, the question is raised as to the definition of a liquid. Certainly, a pot of cold soup may not be reheated on Shabbos, however, what about a solid food that contains liquid, such as fish or chicken which contains liquid gravy, or vegetable stir fry which contains liquid, and so on and so forth of solid foods that also have some liquid and are not completely dry.
B. The law:
The debate: Some Poskim rule that the food must be completely dry and not contain any moisture at all in order to circumvent the cooking prohibition which applies to liquids, and be allowed to be reheated on Shabbos in the permitted ways. [The definition of completely dry is that the solid food is dry to the point that it is not Tofeiach Al Menas Lehatfiach, which means that it’s moisture cannot wet one’s finger enough to make a further finger wet. If the food contains cold moisture past this point, and certainly if the food contains actual cold liquid, it is forbidden to heat it on Shabbos due to the cooking prohibition, even if the food was fully cooked before Shabbos. According to this approach, it is forbidden for one to reheat most foods on Shabbos being that they contain some moisture past this point, and hence one may certainly not reheat chicken or fish which contains liquid gravy, and likewise may not reheat Kugel which is moist to this degree, and all other case of the like.] Other Poskim, however, rule that so long as majority of the food is dry [solid] then it is defined as a solid and not a liquid and hence is permitted to be reheated on Shabbos, so long as both the solid and its liquid was fully cooked before Shabbos. [According to this approach, it is permitted for one to reheat most foods on Shabbos being that they contain only a minority of moisture, and hence one may reheat chicken or fish which contains a small amount of liquid gravy, and likewise may reheat Kugel which is moist, and all other case of the like, and the main application of Bishul Achar Bishul Bedavar Lach would apply only towards soup and the like which contains majority liquid.] Some Poskim explain that the basis of the lenient opinion is in truth from a printing error in the Rishonim, and hence no such lenient opinion even exists and hence this second approach is “Muktzah Min Hadaas,” completely negated from Halacha.
The final ruling: The main ruling for Ashkenazim, and especially for Chassidim who follow the opinion of the Alter Rebbe, is to be stringent in this matter like the first approach to require the food to be dry enough to not wet a finger in order to permit reheating it on Shabbos. Even amongst Sephardim, many Rabbanim are stringent in this matter, and negate any reliance on the lenient opinion. Nonetheless, some Sephardim are lenient in certain cases like the second approach to permit reheating foods on Shabbos which are merely moist and contain a minority of liquid, and hence they may be seen to reheat chicken or fish with liquid gravy on Shabbos. Furthermore, even amongst Ashkenazim, some Poskim rule that if there is only a minute amount of liquid on the food which one has no intent to benefit from, then it may be heated on Shabbos, and hence it is permitted to reheat Kugel on Shabbos even if it has some oil on it that is Tofeiach Al Means Lehatfiach. [However, according to the rulings of Admur, one is not to be lenient in this matter.]
Bedieved: If one transgressed and reheated a food which contains minority liquid, as permits the second opinion above, then if one is simply stringent like the first approach, then seemingly one may be lenient to eat the food. If, however, one holds the first approach to be the only correct Halachic ruling, as rules Admur, then the custom is to prohibit eating this food on Shabbos. Hence, Chabad Chassidim should not eat such food on Shabbos. [See, however, Q&A regarding if heated by another person, such as one’s host]
Non-precooked liquids: The above lenient approach only applies to precooked liquids which have since cooled down, however, if the liquid has never been cooked, then it is forbidden according to all opinions to heat it on Shabbos, even if the food is only slightly moist. Hence, even Sephardim who follow the lenient approach may not heat on Shabbos a Challah which contains frost on it from the freezer, and may not add more liquid to the fish or chicken which will be reheated.
It is forbidden to reheat any solid food on Shabbos if it is wet to the point of wetting another finger. Nonetheless, some Sephardim are lenient in this matter, so long as the food contains only a minority of liquid.
May one who follows the stringent approach [i.e. Ashkenazim, Chabad, some Sephardim] eat food that was heated following the lenient approach [i.e. such as if one is a guest in a Sephardi home which follows the lenient opinion]?
Initially, if a Sephardi who follows the lenient approach is having a guest over who follows the stringent approach, then he should separate some of the food on behalf of his guest prior to heating it, in order so his guest have what to eat, and not need to eat a food which has transgressed the Halachic ruling applicable to him. However, Bedieved, if all the food was heated, such as if the Sephardi host is completely unaware of the different rulings on this subject, then seemingly the guest may be lenient to partake in the food, if its solid and minority liquid was fully cooked before Shabbos. If it contains majority liquid, such as a soup, or contains liquid that was never heated before Shabbos, then [even] Sephardim may not eat it on Shabbos.
 See Shabbos Kehalacha Vol. 1 p. 24 and p. 142; Piskeiy Teshuvos 318:32 footnote 266-268; Halacha Berurah [Yosef] 318:88 [p. 224]
 Opinion and final ruling and custom in Admur 318:9; Michaber 318:4; final custom in Rama 318:15; Rashi; Rabbeinu Yonah; Rosh
Other opinions: Some Poskim rule that even if [the precooked liquid] has [already] completely cooled down there is no [prohibition in] cooking it after [it having been previously] cooked. [2nd opinion in Admur ibid; Rama 318:15; Rashba; Ran; Magid Mishneh] The custom is to be stringent like the first opinion. [Admur ibid; Rama 318:15]
 1st opinion in Admur ibid; Michaber 318:4; Rashi; Rabbeinu Yonah; Rosh Beis Yosef; M”A; M”B 318:24
 Admur 253:19 “even if the food [which one wants to return] is completely cooked but it has already completely cooled down, then it is forbidden to return it in all cases, even if it is a type of food which reheating it does not consist of a prohibition of cooking, such as is the case with a dry food that has no liquid at all that is fully cooked”; Admur 318:11 “Dry food which contains no liquid at all is [permitted to be] cooked after having been previously cooked as long as it was already fully cooked, even if it completely cooled down.”; Admur 318:17 “Nevertheless, ox meat is forbidden to place inside a Keli Rishon [that is off the fire] as although the meat [itself] will not cook, nevertheless the moisture that is on it will cook. Although if [the meat] is completely dry and does not have on it any moisture at all [then it is allowed].”; Siddur Admur regarding congealed fats; Chasam Sofer 74 “Only if the coffee is completely dry and contains no moisture at all”; Divrei Nechemia p. 36 in Hosafos “This opinion [if the Minchas Kohen] is Muktzah Min Hadaas and is based on a mistaken Nussach in the Rabbeinu Yerucham.” ; Shevisas Hashabbos 318:74; Ketzos Hashulchan 124 footnote 37; Igros Moshe 4:74:7; Or Letziyon 2:30:13; Tevuos Shemesh O.C. 66; Implication of P”M 318 M”Z 15 and 253 A”A 32 and M”B 318:32
 Ketzos Hashulchan 124 footnote 37
 Admur 613:14
 Nussach of Rabbeinu Yerucham Nesiv 12:3 p. 69, as brought in Beis Yosef 253; Minchas Kohen Mishmeres Hashabbos 2:2; Elya Raba 318:11 brings the Minchas Kohen and concludes with a Tzaruch Iyun; Iglei Tal Ofeh 34; P”M 253 M”Z 13 in name of Minchas Cohen ibid and A”A 41; Kaf Hachaim 318:62; Yaskil Avid 3 O.C. 10-12; 4:15; 8 p. 178; Yechave Daas [Chazan] 2 24:2; Mayim Rabim O.C. 21; Daas Torah 318:15; Har Tzevi 1; Yabia Omer 7 O.C. 42-6 [and many other places listed in Halacha Berurah ibid Birur Halacha 108 and footnote 116]; Chazon Ovadia Hilchos Chanukah p. 19; Rav Chaim Sheinberg in Sefer Hazikaron Rav Zaluti p. 657; Rav Karp in Hilchos Shabbos Beshabbos 1:8 p. 489 and Mishmeres Moed Shabbos 39b; Poskim in Halacha Berurah ibid footnote 114
 The reason: This is because when majority of the food is a solid one does not have in mind to cook the liquid and in such a case one may even initially rely on those Poskim that are lenient to say there is no Bishul after Bishul by liquids. [Iglei Tal ibid]
 However, see Piskeiy Teshuvos ibid footnote 266 that even according to the Minchas Kohen one may only be lenient by liquid that is Tafel to the food, and not if the liquid is already separate on its own and the solid is simply sitting within it. So likewise rules Halacha Berurah ibid, that even those who are lenient may only do so if there is very little gravy, and not if the food is sitting in a puddle of liquid, even if the liquid is minority.
 Divrei Nechemia ibid; Hagahos Rav Bamburger; Or Letziyon ibid; Poskim in Halacha Berurah ibid Birur Halacha 108
 See ruling of Chasam Sofer and Igros Moshe ibid
 See rulings of Admur ibid
 Or Letziyon ibid; Rav Ezra Atiya; Menuchas Ahavah 2:10-47; Rav Yaakov Yosef z”l severely negated the lenient opinion of Rabbeinu Yerucham and told Sephardi askers they cannot rely on it Chas Veshalom even if there is a small amount of gravy on fish. [however, in other Shiurim he was heard to be lenient, Vetzaruch Iyun]; Sephardi Poskim and Rabbanim in Halacha Berurah ibid Birur Halacha 108
 See Halacha Berurah in great length for the limitations even according to the lenient opinion, and that we do not follow a simple majority, such as for example, even those who are lenient may only do so if there is very little gravy, and not if the food is sitting in a puddle of liquid, even if the liquid is minority, and that so he was told by his father Rav Ovadia Yosef.
 So concludes Kaf Hachaim ibid; Rav Ovaida Yosef and Halacha Berurah is lenient if there is very little gravy, although concludes that one who is stringent is blessed.
 Piskeiy Teshuvos ibid and in footnote 268; Letters of Gedolei Yisrael compiled in Maor Hashabbos 7:13; Shevet Halevi 1:67; Teshuvos Vehanhagos 1:207; Halacha Berurah ibid
 See Admur 253:25 “since there are opinions which allow this to be done even initially as will be explained in 318, [therefore] one may rely on their words after the fact (to not forbid the food placed on by the gentile, even if the Jew commanded him to do so)”
 Admur 318:9 “If the liquid completely cooled down, we are accustomed like the first opinion even regarding a case that one already heated it [and thus the food would be forbidden to be eaten] as was explained in chapter 253 [Halacha 25].” Vetzaruch Iyun as there the Alter Rebbe rules in parentheses that even if a Jew himself heats up liquid food it is allowed to be eaten being that there are opinions which permit this even initially. Meaning the above allowance applies even if the Jew himself placed it there, and certainly if a gentile placed it there based on his command. Perhaps however there in 253:25 the Alter Rebbe is mentioning the letter of the law, that it is permitted, while there he is mentioning the custom, which is to be stringent.
 So rules Admur 253:25 regarding if a gentile heated a complete Davar Lach, and seemingly even more so should this apply to if another Jew heated it when there is minority liquid which some Poskim permit even for a Jew to heat [See Admur there: “(even if the Jew commanded the gentile to return it) if he returned it (even the Jew himself) to an area where there are opinions which permit this to be done even initially, such as to place it near an oven that is not swept or covered, or next to a bonfire, food that was completely cooked but has liquid which has completely cooled down, and [by placing it near the fire] it heated up there until it became Yad Soledes, then even though [transgressing such a prohibition according to some opinions] makes one liable to bring a Chatas offering (for the Jew) [if the Jew placed the food there], nevertheless, since there are opinions which allow this to be done even initially as will be explained in 318, [therefore] one may rely on their words after the fact (to not forbid the food placed on by the gentile, even if the Jew commanded him to do so).”]; See M”B 318:2 in name of Peri Megadim
 As according to all final opinions, a majority liquid food is forbidden to be reheated on Shabbos, and according to Sephardim, this is a Biblical cooking prohibition and hence the food is forbidden due to Maaseh Shabbos. However, according to Ashkenazim, perhaps even here one can be lenient, as our main opinion is that Ein Bishul Acher Bishul Bedavar Lach, and perhaps one may be lenient if another Jew does it, just as we are lenient if a gentile does it. Vetzaruch Iyun!