Translation:Shulchan Aruch/Orach Chaim/259
259ː Several Laws Governing Insulation and Moving them. Contains 7 seifim.
1 It is forbidden to move muchin (meaningː any soft substance is called "muchin", e.g., cotton, and soft wool plucked of an animal, and remnants of worn out clothes) with which one insulated on the spur of the moment. Rather, he shakes the cover and they fall; e.g, part of them is uncovered, for this 'moving' is only from its side. And if he designated them for this, it is permitted to move them. But if he insulated with fleece wool, even if he did not designate them for this, it is permitted to move them. And these words refer specifically to mere fleece that is not set aside for commerce. However, if he placed them in a storehouse for merchandise, they need to be be set aside. And if one insulated with them without them being set aside, one shakes the cover and they fall off, that is to say, that he takes the cover of the pot that has the status of a vessel on it. And even though they are on top of it, we are not worried about it, because it did not become a base for them.
2 Those who place stones and bricks around the pot need to permanently designate them for this forever, for as long as he did not designated them, they are not important to him and he casts them away. Therefore, it is forbidden to move them, unless he will set them aside and designates them for this.
3 One who insulates in a container full of fleece wool that are forbidden to move, and he removed the pot, he could return it as long as the hollow did not break down. And if it broke down, he should not return it. And even initially, one could remove it with the intent of returning it if it will not break down. And we are not concerned that he may return it even if it will break down. And there are those who say that even if one insulated with a substance that is permissible to move, if the hollow broke down, one should not return it, because the pot will need to make a place for itself when he returns it, and it's like one who insulates on Shabbat.
4 One insulated with something that is not moved and covered its mouth with something that is moved – one exposes the cover, and grabs the pot and removes it.
5 One insulated and covered with something that is not moved – if part of the pot is exposed, one takes it and returns it, and if not, he does not take it.
6 A festival that falls on the Eve of Shabbat – there is one who forbids to insulate with stones, because this is like building; and there are those who permit.
7
The oven in which the warm food is placed, and its opening is blocked with a board which is pasted [meaningː smoothed] with mud – it is permitted to break apart that seal so as to remove the warm food, and to return and seal it. And if it has burning coals, it is permitted by a heathen.
Gloss: And there are those who are stringent not to break the seal of the oven that is sealed with mud by a Jew if it is possible to do it by a heathen. And likewise, if it is possible to do it by a minor Jew, an adult Jew should not do it. And if it is not possible, an adult should do it by a slightly different manner, and this is the custom (Terumat HaDeshen, No. 305; and Agur). And it seems to meː this that it is permitted to return and seal the over, refers to during the day, for all the pots are already cooked as much as needed. However, at night, close to the time of its insulation – for one can be doubtful that maybe the pots have not yet been cooked as much as needed – it is forbidden to seal the oven because one causes it to cook as was explained, Siman 257, Seif 4. And even via a heathen it is forbidden, as was explained above, end of Siman 253. (And other laws regarding returning on Shabbat – see later, Siman 318).