Commento su Hallah 4:6

נוטל אדם כדי חלה – [A person] who wishes to knead a few batches of dough of impure doubtfully-tithed [dough -for Hallah], he can establish their Hallah from pure dough whose Hallah had not yet been dedicated, and that it will be this particularly batch of ritually pure dough that will be established for Hallah on all the dough that he will need from the ritually impure doubtfully-tithed [dough- for Hallah].

Introduction This mishnah is complicated and I will explain it entirely, as opposed to line by line, below.

עד שתסרח – this particular batch of dough and that it won’t be appropriate for human consumption, for regarding doubtfully tithed produce, the Rabbis were lenient [to permit] dedication from something pure [to fulfill the liability] on that which is impure and from that which is not nearby. And they (i.e., the Rabbis) were also lenient to dedicate from that which was of poor quality [to fulfill the liability] on something that was good, and the Hallah of doubtfully-tithed [dough] is that grai which a person buys from an ignoramus who feeds it to the poor and to troops on the march, as it is taught in the Mishnah (Tractate Demai, Chapter 3, Mishnah 1): “We feed the poor Demai produce and the .troops on the march Demai produce.” But the Hallah that we separate from it is Hallah of doubtfully-tithed dough.

A man may take the requisite amount for hallah out of [clean] dough from which hallah has not [previously] been removed in order to remove it in a state of cleanness in order to go on separating [hallah] from it for [unclean] demai, until it becomes putrid, since hallah for demai may be taken from clean [dough] for unclean [dough], and from [one dough for another dough] which is not in close proximity. This mishnah refers to a person who sets aside dough in order for this dough to count as hallah for other dough that he will receive in the future from which he doesn’t want to bother separating hallah. The dough that he will receive in the future is “demai” meaning it was received from an am haaretz, one who doesn’t observe these laws, and therefore we have to be concerned lest hallah has not been removed from it. However, the laws are usually more lenient when it comes to demai. Generally, one cannot take hallah from one batch of dough in order to exempt different dough unless the two batches are in close proximity. When it comes to demai this is permitted. Secondly, one cannot separate hallah from clean dough in order to exempt unclean dough. Again, when it comes to demai this is permitted. The demai dough that he receives from the am haaretz can be assumed to be impure, and nevertheless he can separate pure hallah in order to exempt impure dough. To return to our situation, this person sets aside dough in order for that dough to count as hallah for demai dough that he will receive in the future from an am haaretz. He can do this until the dough becomes putrid. However, he is concerned lest the dough that he sets aside to count as hallah will become impure. The problem would then be that this dough has not had its hallah removed and by the time he takes the hallah out, it will be impure hallah. To prevent this from happening, he should immediately take the hallah out of this batch of dough. This way at least the hallah for this dough will be pure.