We continue with Maseches Avodah Zarah, chapter 3 mishnah 9, dealing with the prohibition of deriving benefit from an asheirah - a tree used for idolatry. The mishnah opens: "Natal mimenah eitzim" - a Jew who took wood from that tree, the wood is forbidden to derive benefit from. (If a gentile took it and thereby actually nullified the tree, the law is different, as we will learn in the next mishnah.)
Heating an oven with forbidden wood:
What is the law if he used it to heat his oven? Ovens in the time of the Mishnah were cone shaped structures made of earthenware, attached to the ground. The first firing of the oven is what prepares it for use: the heat hardens the clay, draws out its moisture, and from then on the oven works better. It turns out that the oven itself is improved by the wood burned inside it, and when this is a first firing with forbidden wood, the entire oven benefits from the forbidden item in a way that would render all of it forbidden.
The mishnah therefore distinguishes between a new oven and an old one:
"Im chadash - yutatz" - a completely new oven that has never been used becomes forbidden because of the improvement it received, and the law is that it must be broken down.
"Ve'im yashan - yutzan" - an oven that has already been used at least once has already dried out and its clay has hardened, so it gains no additional improvement. Even so, the heat produced by the burning wood is forbidden, and therefore one must let it cool and wait until it has cooled down before baking his bread in it.
The bread baked in the oven:
If he did not do so - "Afah bo es hapas - asurah bahana'ah". The heat produced by burning the wood is, as it were, invested in the bread, and the bread serves as the container of the forbidden item. This is what is called "the improvement of forbidden wood in the bread": the energy that was stored in the wood was released and absorbed into the body of the baked loaf, so that the benefit from the forbidden wood is found within the bread itself. For this reason the entire loaf is forbidden to derive benefit from.
"Nis'arvah ba'acheiros - kulan asuros bahana'ah":
If that forbidden loaf became mixed with other loaves - for example, one loaf baked in this oven that became mixed with nine permitted loaves - all ten loaves in the mixture are forbidden to derive benefit from. This is a great novelty, since the usual rule is that a mixture in which there is no blending of flavors, known as "dry with dry," and all the more so when it is a substance mixed with its own kind - bread with bread - is nullified in a majority, and when the majority is permitted and the minority forbidden, everything is permitted. Here we are stringent, and this is puzzling.
There are two approaches among the Rishonim in explaining this:
There is a list of nine types of items that are not nullified in a majority, and one of them is "an item that is counted" - an important item that is counted one by one. Such is the case with loaves that a woman bakes for her household: each loaf stands on its own and is counted by itself, and it is therefore too significant to be nullified. According to this approach, if the loaves came off the production line of a bakery, where loaves are sold by the dozen and are not counted one by one, the law might well be different.
The Sages were especially stringent in everything connected to deriving benefit from items of idolatry, and therefore they were stringent here as well not to allow nullification in a majority.
The view of Rabbi Eliezer and the argument of the Sages:
In any case, "Rabbi Eliezer omer: yolich hana'ah l'Yam haMelach" - Rabbi Eliezer says: he should take the benefit and cast it into the Dead Sea. In his view, once the forbidden loaf became mixed into permitted loaves, the prohibition is only rabbinic, since by Torah law it is nullified in the majority. Therefore it is enough for him to take the value of the forbidden loaf (and some explained: the value of the forbidden wood) and cast it into the Dead Sea. Once he has lost that amount, he no longer derives any benefit at all from the mixture, for whatever he gained from that loaf he lost by what he threw into the sea, and the two cancel each other out.
There is something here of redemption, similar to Maaser Sheni, which carries sanctity and yet can be redeemed onto a coin, the coin then being brought up to Jerusalem and spent there. Sanctity can be converted and transferred, and Rabbi Eliezer likewise seeks to transfer the status of the prohibition onto the coins thrown into the sea.
But the Sages reject this entirely: "Amru lo: ein pidyon la'avodah zarah" - they said to him: there is no redemption for idolatry. There is no concept of redemption when it comes to the prohibitions of idolatry, and there is no way whatsoever to remove the prohibition from that loaf or from the mixture, and therefore everything remains forbidden.
The halachah: The ruling follows Rabbi Eliezer. A single loaf baked with forbidden wood is certainly forbidden, and this is more stringent than the rule of 'this and that cause it' - which in itself is permitted - because here the improvement contributed by the wood enters into the loaf itself. But a mixture is permitted according to Rabbi Eliezer, provided that he throws into the sea the value he would have gained from it. There is a dispute among the later authorities as to whether one may eat the loaves themselves or only sell them to others, and this is not the place for it.
The second part of the Mishnah - the weaver's shuttle:
The second part of the Mishnah repeats exactly the same principle, except that instead of firewood he took wood from the tree to make from it a weaving implement, and wove a garment with it. The language of the Mishnah is: "Natal heimenah karkar - asur b'hana'ah. Arag bo es habeged - habeged asur b'hana'ah. Nis'arev b'acheirim v'acheirim b'acheirim - kulan asurin b'hana'ah" - if he took from it a weaver's shuttle, it is forbidden to derive benefit from it; if he wove a garment with it, the garment is forbidden to derive benefit from; if it became mixed with others, and those with others, all of them are forbidden to derive benefit from. The karkar is a kind of weaver's needle, and once it is made from the wood of an asherah it is forbidden to derive benefit from it; and once he has woven a garment with it, the entire garment becomes forbidden to derive benefit from, and even if it became mixed with others, and even if that mixture became mixed into another mixture, it is never nullified, and everything is forbidden.
Why did the Mishnah teach the law twice? Because with the shuttle the stringency is far greater. With the bread, at least the improvement contributed by the wood is found within the loaf itself; here, however, the shuttle is not consumed and is not absorbed into the garment at all, but serves merely as a tool for producing the garments - and nevertheless we are stringent. Both cases are therefore necessary: Rabbi Eliezer is lenient in both, and the Sages are stringent in both.
At first glance the novelty here lies in a mixture that became mixed a second time, but in truth there are versions of the text in which this phrase does not appear at all, and versions in which it appears in both cases - both with the bread and with the weaver's implement. Moreover, if that were the novelty, the Mishnah could have said that the mixture of loaves became mixed with additional loaves, so why did it need the weaver's implement? Clearly, then, this does not account for the need for both cases.
In the Gemara we find a dispute among the Amoraim regarding the law when a minority of one mixture became mixed into the majority of a second mixture, since there is here something of a double doubt. In any case, according to the Sages a forbidden item remains forbidden forever, and even though the mixture goes on to be mixed into further mixtures, everything remains in its doubtful status and everything is forbidden.
Rabbi Eliezer, however, taught here as well: "Yolich hana'ah l'Yam haMelach" - he should take the benefit and cast it into the Dead Sea. It is enough to throw the value of the forbidden item into the sea in order to offset the benefit. And the Sages again responded: "Amru lo: ein pidyon la'avodah zarah" - they said to him: there is no redemption for idolatry. The prohibition cannot be transferred onto the coins. Here too the halachah follows Rabbi Eliezer: with a mixture, a person may throw away the value and keep the mixture in his possession, and it turns out that he derives no benefit at all from what is forbidden.