Sources and Reasons:
The Gemara in Shabbat (40b) explains that it is permitted to take a vessel containing oil and place it inside a larger vessel of hot water on Shabbat (where there is no issue of cooking, such as when it is a kli sheni). One must examine why this does not involve the prohibition of hatmanah. Maran the Chazon Ish (siman 37, se’if katan 32) wrote that the prohibition of hatmanah does not apply to water or food within a vessel, and Chazal did not decree a prohibition of hatmanah in this case. Although the Mishnah Berurah (siman 258, se’if katan 2) prohibits insulating even within a vessel when it is entirely covered by it, and the Aruch HaShulchan (siman 258, se’if katan 3) likewise prohibits it, and Shut Shevet HaLevi, vol. 3 (siman 47), wrote that the custom was to prohibit it, nevertheless Maran HaRav, in his sefer Chazon Ovadia, vol. 1 (p. 62), wrote that the Chazon Ish is worthy of being relied upon.
Additionally, one may combine the ruling of the Rema (siman 257, se’if 7), that anything which is completely raw or fully cooked may be insulated, just as it may be left on the heat source. Here, if the eggs or jachnun are fully cooked or completely raw, there is room to be lenient. Furthermore, the Beit Yosef (end of siman 253) cites the Rishonim that anything insulated for the following day is permitted even in something that adds heat. So too wrote the Birkei Yosef (beginning of siman 253), adding that this is the custom.
One may also combine what is written in Shut Or LeTzion, vol. 2 (chapter 17, ot 13), that the laws of hatmanah do not apply to food within food, but only to cushions and pillows. He brought proof from the Shulchan Aruch (siman 318, se’if 4), which states that something dry that was fully cooked may be soaked in hot water on Shabbat. Here as well, although it is inside a pot, the pot is insulated within water, which is food.
Furthermore, it appears to me that the reason for placing the food, as well as the eggs, inside a pot is so that the water will not become soiled. Likewise, jachnun is placed in a pot rather than directly in the hot water so that it does not become a doughy mass and lose its flavor. In such a case, one may combine the ruling of the Shulchan Aruch (siman 257, se’if 2): “Nevertheless, placing vessels upon a cooked dish in order to protect it from mice or to prevent it from becoming soiled with dust is permitted, for this is not like insulating in order to heat it, but rather like guarding it and placing a cover upon the pot.” End quote. The reason for this leniency is that one does not intend to insulate it. Although this is a pesik reisha regarding a Rabbinic prohibition, why is it not prohibited at least according to those opinions that maintain that a pesik reisha is prohibited regarding Rabbinic laws? It must be that since the concern is only lest one insulate in coals and lest one stoke the coals—although both are one concern, as explained by the Ran—Chazal saw fit to decree only where one’s intent is to heat the food. In that case, there is concern that one may come to insulate in coals, which is likely. However, where the purpose of this insulation is to protect the food from becoming soiled, they were not concerned.
This response was translated automatically from Hebrew and has not yet been reviewed by a person. Therefore, it may contain inaccuracies and should not be considered a definitive reference.
