Siman 461

An oven in which they baked chametz—it requires a thorough libun to render it kosher for Pesach. And one must be careful when heating it in order to bake matzah in it, that the coals should travel over the entirety of it from its beginning to its end, and also on its rim. And it is not sufficient for him that the flame dominates there; for as it absorbs, so it expels, and since the absorption was by means of coals, therefore the expulsion must also be so. And it is necessary that in the entire oven sparks should be flying from it. And even if they heated it several times before Pesach—it is of no avail when his intention was not for the sake of the Pesach preparation, for certainly he did not ensure that the coals were over the entirety of it, and it is possible that it was so that they did not travel over the entirety of it. Nevertheless, post facto when they baked matzah—one should permit in such a case when they heated it several times, even if not for the sake of preparation, for it is probable that at any rate one time the coals were over the entirety of it. But if they heated it one heating without the intention of preparation—it is of no avail even post facto. (Magen Avraham, subsection 1. And regarding what he compares to milk in Shevuot—I am astonished, for there they bake and cook in vessels and not in the oven itself, which is not the case with chametz and matzah. And it requires further study; be precise and you will find it light.)

And behold, according to the essential law, when they stoke the oven for the purpose of kashering—it is permitted to bake matzah with this stoking. Nevertheless, the custom is not so, for after the stoking of the kashering they do not bake in it; rather, they perform another stoking for the matzah, after the oven cools. And it is a beautiful custom, and it is good and upright to do so, for perhaps there was actual chametz there and it was burnt, and that fire benefits the matzah, and it turns out that he benefits from chametz. However, this reason is only relevant after the time of its prohibition, as I wrote in siman 445. And there is another reason: that if he bakes with this stoking—there is a concern that he will not stoke much, so that the bread will not be scorched. And although these decrees are not found in the Gemara, nevertheless, since they conducted themselves so on their own—it is a valid and upright custom. (See Magen Avraham subsection 3, who also raised the issue of meat and milk, see there. And this is also from the reason we wrote in the previous section. Examine it and you will find it simple.)

There are those who are accustomed to making a new floor in the oven, and it is a beautiful custom. Through this, it does not require heating. And even though there is absorption of chametz above and from the sides, nevertheless, for this the heating that they will heat to bake the matzah is sufficient, for the flame will rise there and expel [the absorption] (Magen Avraham, subsection 2). Therefore, for the usage that is on top of the oven and on the sides of the oven—this is not effective. And how much should the thickness of the new floor be? The Levush wrote: like the thickness of a finger. And his reason appears to be that even in a food item, [the absorption] does not enter more than the thickness of a finger, which is "kedei netilah," as I wrote in Yoreh Deah siman 105. And regarding chametz, there is no fattiness that would cause it to permeate through the whole of it.

A new earthenware tapka—and this is a vessel under which one kindles fire from below and bakes upon it from above, and it is not common among us—it is permitted to bake matzot upon it, for since the fire dominates beneath it, it becomes well-heated, even though the flame does not rise upon it. And the bread is baked immediately, and does not come to a state of leavening. One only needs to be careful to kindle fire beneath it first, until it is well-heated, and afterwards he should attach the bread upon it. And so too when one bakes in a pan without liquid, he should be careful to kindle fire beneath it first, until it is well-heated. And afterwards he should attach the bread inside it, for if he attaches the bread beforehand, and afterwards heats it—there is concern lest before it is well-heated the bread will leaven. And even ex post facto one should be stringent, unless he has no other bread (see Chok Yaakov, subsection 7). And so too it is forbidden to place matzah in an oven upon paper. But ex post facto—there is no concern, for certainly the fire dominates it through the paper, which is thin (ibid.).

It is good to be stringent and to protest against baking a cake in hot ashes, and likewise that one should not bake in the sun, as there is a concern that they will become chametz before they begin to bake. And if one transgressed and baked in hot ashes—it is permitted for eating, and one fulfills his obligation with them on Pesach. But in the sun—one does not fulfill his obligation, because that which is baked in the sun is not called "bread." And the Torah said "bread of affliction." And it is not called "bread" unless it is baked by fire in an oven or in a pan without liquid, and not that which is baked in the sun. And to eat—it is permitted ex post facto, for since the heat of the sun there is so strong that it is baked—it is obvious that it does not allow it to become chametz (the Harav Zalman).

And so too if it was baked in the ground, such as troknin, which is a pit made in the floor of the stove, and one places there flour and water mixed together and it is baked there, even though its batter is very thin and it does not have the form of bread; and therefore one does not recite "Hamotzi" over it unless he established his meal upon it, as I wrote in siman 168; nevertheless, a person fulfills his obligation with it on Pesach even ab initio, because this is "bread of poverty," like a poor person who does not have an oven and bakes his bread in the ground. And he recites over it "Hamotzi" and Birkat HaMazon, for on Pesach it constitutes establishing a meal.

Matzah that was baked until the point that if one breaks it, no threads are drawn from it—one fulfills the obligation with it. And even if it crumbles when it is handled—one fulfills the obligation with it, since no threads of dough are drawn from it. But when threads are drawn from it—one does not fulfill the obligation with it, for it is not bread but rather dough. And the sign for this is: that its surface has formed a crust. And one must be careful not to remove it from the oven before this time and return it, because it could come to a state of leavening. But after this time—one may remove and return it, because then it is considered as baked. And if there is a doubt whether threads are drawn or not—one should be stringent. And know that this cannot be recognized except when the bread is hot and not when cold. And then one must see the crusting of the surface, for this is recognizable even when cold. And if one inserts a finger and the finger does not stick—it is a sign that no threads are drawn (Chok Yaakov, subsection 10). And there is one who says that if one removed it from the oven before the point where threads are no longer drawn—it is forbidden immediately (Taz and Chok Yaakov), for through the heat it leavens immediately. However, in a case of doubt whether threads are drawn, one may be lenient (ibid.). And in our matzot, it is not common at all that threads should be drawn from them.

A person fulfills the obligation with matzah soaked in water. This is specifically when it has not dissolved, but if it dissolved – he has not fulfilled the obligation. As we say in Chullin (120a): If one liquefied matzah and swallowed it – he has not fulfilled the obligation. And so too if he cooked it, even if it did not dissolve – he has not fulfilled the obligation. Therefore, one should not place it in a kli rishon because it cooks, and also in a kli sheni one should be stringent if it is not for a necessity (Magen Avraham subsection 8), for through cooking the taste of matzah is nullified. And even though we hold that if one swallowed matzah he has fulfilled the obligation, for we do not require that he taste the taste of matzah as I wrote in siman 475 – that means we do not require that he taste the taste of matzah in his mouth like maror, as I wrote there. But nevertheless, there must be the taste of matzah in his innards, and through cooking it is as if it is not matzah at all (Taz subsection 2). And this soaking that we mentioned, some say it is specifically in water and not in wine, for it nullifies the taste of matzah (Magen Avraham subsection 7), unless it is out of necessity. And some say that it is all the same (Taz ibid.), for wine also does not nullify the taste of matzah, and so too in broth. It is only that they must not be hot from a kli rishon. And know that even in water it was only permitted for a sick person or an elderly person, who are unable to eat dry matzah, or one whose teeth are damaged. But one who is able to eat it dry – soaking was not permitted for him, for the primary taste of matzah is in its dryness.

If they baked matzah and chametz in one oven – it is not forbidden unless it touched the chametz. For on account of the aroma of chametz it is not forbidden, even according to the one who forbids the aroma of chametz on Pesach in siman 447, for specifically the aroma of fattiness is called "aroma," and not the aroma of bread (Magen Avraham subsection 9). And if they touched one another – one removes from the place of contact the amount of "k'dei netilat makom," which is like the thickness of a finger. For at most it does not absorb more than this measure, as there is no fattiness here at all for us to fear diffusion. And it appears to me that if they were baked in one pan – it is all forbidden, for the entire pan is absorbed with chametz, and the absorbed substance enters into the entire matzah. And it requires "k'dei netila" in its entirety, and in its entire thickness there is not the thickness of a finger. Therefore it appears to me that even in one oven which does not forbid as has been explained – this is when they were not on one level, and it is like two vessels. But if they baked chametz and matzah on one level – it is all forbidden. Therefore, if the entire oven is only one stone – it is forbidden.

Our teacher, the Rema, wrote in section 5: Matzah that was folded in the oven and is stuck, to the extent that the fire does not rule there—we forbid it during Pesach. However, the rest of the matzot in the oven are permitted. And before Pesach, one need only forbid the place that is stuck. Thus far his words. And specifically in a case where it is truly stuck, meaning that part of it folded over another part and truly stuck together, for then the fire does not enter between them. But in cases where they are adjacent without sticking, there is no concern at all (Taz subsection 3 and Magen Avraham subsection 11 in the name of the Maharil). And there is one who forbids if its surface did not crust (ibid. in the name of the Bach), as this is a sign that it was not baked there. And this applies to a folded matzah where there is a visible flaw before us, but regarding an ordinary matzah, there is no concern if its surface did not crust (ibid.), for sometimes there is dough that does not take on a crust. And before Pesach, one need only forbid the place that is stuck, and he casts it away. And even if there is not sixty in the entire matzah against the place that is stuck, since it is not absolute chametz, and it is not something that melts and becomes mixed, and it did not spread throughout the entire matzah. And there are those who require sixty, but the primary view is like the first opinion, for so the great authorities agreed (Taz subsection 5, and Chok Yaakov subsection 18, and see Magen Avraham subsection 12). And a folded matzah that touched its fellow at the place of the fold—it forbids it to the extent of a peel, but not at the place of the fold—it does not forbid (ibid.).

And I have a question regarding this: A doubled and truly attached matzah, which we have forbidden because the fire does not enter between the attachments, what reasoning is there in this? For if the matzah were twice as thick as it is now, we would not have forbidden it if it is not thicker than a tefach. And now that it is doubled, why should we care? On the contrary, when it is truly attached—it is one thick matzah. And in truth, the law of doubled matzah is not found in the Gemara at all. And it must be said that there was a tradition among the early authorities that two lumps of dough attached to one another—the fire does not enter well between them. And in my humble opinion, the opposite would seem to be true, that when they are attached to one another—there is no concern at all, for they are one dough. And when they are not attached—the fire does not enter between them. But since our teachers did not say so, our humble opinion is nullified before their great opinion.

He further wrote: A matzah that is swollen in its middle is forbidden. However, if a crust rose upon it, in the manner that it rises upon bread during the time of baking, it is permitted. Thus far his words. And there are two interpretations of this: The first is that the matzah is swollen in its middle and divided into two, with a hollow space between them. And the second is that the entire matzah in its middle rose upward like a mountain. And some have written that specifically according to the second interpretation is there a concern of chimutz, for such is the way of leavened bread to raise itself upward due to the strength of the chimutz. But when it is divided into two, this comes because it was not perforated well, and it is nothing (Taz, subsection 6). And some forbid even according to the first interpretation, for when it is very swollen in its middle, there is a concern of chimutz (Magen Avraham, subsection 13). However, one should only forbid that matzah alone, and no more. And in our matzot there is no concern of a swollen one at all, for they are thin. And sometimes it is slightly swollen due to a lack of perforations, or due to the strength of the fire that dominates its thinness and raises it, as is visible to the senses. And in our days we have never forbidden on account of a swollen one; and only in the case of a stuck one do we remove the stuck part with a bit more of what is adjacent to it and discard it. And it does not require burning, for it is not chametz (see Magen Avraham, subsection 12).

He further wrote: If two mitzvot are lying one upon the other in the oven before their baking – they are forbidden, for it is like a doubled matzah. And so one must be careful that they do not touch one another in the oven while they are moist, for the fire does not rule over the place of their contact, and they come to a state of chimetz. Thus far his words. And post facto, if they bit into one another, and both of them touch the oven below – then the heat of the fire rules well below and it is baked nicely, and it is permitted (ibid. subsection 14 in the name of the Rashal). (The Magen Avraham subsection 13 elaborated on the matter of a hole in the matzah, that this is forbidden, and it is a sign of chimetz, and also regarding blezlach, see there. And we do not know at all of the matter of the hole, and also tiny blezlach must necessarily be in all the mitzvot.)