Last week we discussed the history behind the gezeirah (decree) of pas akum (non-Jewish bread). This week we will begin discussing the basic halachos.
The Shulchan Aruch in Yoreh Deah 112:1 says that Chazal forbade eating the bread of a non-Jew. The gezeirah only applies to bread made of the 5 main types of grain (wheat, barley, rye, oats and spelt). Breads made out of rice, corn, or anything else are permissible.
What do we mean when we say "the bread of a non-Jew?" Does it mean that the non-Jew owns it, baked it, or perhaps something else? The Shach says that it is implied in the Shulchan Aruch and the Rema throughout the siman (section) that the issur (prohibition) of pas akum only applies to bread baked by a non-Jew, but not to bread simply owned by a non-Jew. If the non-Jew kneaded or braided the bread, it is still permissible. (This follows the opinion of the Rambam and the Rashba, and not going like the Ran and the Tur, who say that if the non-Jew is involved with any part of the bread-making process, this makes it pas akum.)
The Shulchan Aruch does not distinguish between bread made under Jewish supervision, or not. The Shach asks: In the case where we didn't see the bread being made, why do we even need the gezeirah of pas akum, the bread should be forbidden simply because it might have been made with non-kosher ingredients?! The answer is that in the times of the Shulchan Aruch and those before him, bread was only made from flour and water. There were no other ingredients, so there was no concern that anything non-kosher had been introduced. It is only because of the gezeirah of pas akum that the bread is forbidden.
The Shach has another kasha (difficulty): Even if the ingredients were kosher, what about the baking pan the non-Jew used? Surely the taste of the non-kosher food previously made on the pan had been absorbed into the pan, which would then be reabsorbed by the bread? The Shach answers that there is no concern of bliyos (absorbed non-kosher taste) because "stam keilim ainom bnei yoman." This means that the non-Jew's utensils are assumed to not have been used for at least 24 hours. After 24 hours, the non-kosher taste in the utensils goes bad (this is called "nosein taam lifgam"), and this undesirable taste can no longer render anything non-kosher (in most cases).
But there is more: Even if the keilim (utensils) have not been used for 24 hours and hence the taste has gone bad, we have the problem of "ain mevatlin issur lechatchilah" (we don't nullify non-kosher materials a priori). This means that if a Jew owns a non-kosher pot, it is not sufficient to wait 24 hours so that the taste will go bad, and then to use it afterwards. Rabbinically, one has to kasher the pot. So why don't we require the non-Jew's baking pan to be kashered for the same reason? The answer is that the principle of "ain mevatlin issur lechatchilah" only applies when a Jew is doing the cooking/baking. A non-Jew is not bound by it. So as long as the utensils are not bnei yoman, they are nosein taam lifgam and there is no problem of non-kosher taste going into the bread.
So, in summary, bread that was baked by a non-Jew, out of one of the 5 main types of grain, even if all the ingredients and utensils were kosher, is forbidden to be eaten. This is known as the gezeirah of pas akum. In the coming weeks, we will discuss the details of pas akum, including the well-known topic of pas palter, bread baked by a non-Jewish baker for commercial purposes.