Мидраш к Бамидбар 15:21

(Bamidbar 15:21) "Of the first of your dough": Why is this written? (i.e., It is already written in the preceding verse.) From (the preceding verse) "The first of your dough," I might understand it to mean the first of (all) your doughs. It is, therefore, written "Of the first of your dough" — part of it and not all of it. (Ibid. 20) "The first of your dough": To include leket (Vayikra 19:9), shikchah (Devarim 24:19), and peah (Vayikra 19:9) as subject to challah. For it would follow (otherwise), viz.: If other produce (i.e., rice and millet), which is subject to ma'aser, is exempt from challah, then leket, shikchah, and peah, which are not subject to ma'aser, how much more so should they be exempt from challah! It is, therefore, written "the first of your dough," to include leket, shikchah, and peah as subject to challah. Or, let other produce be subject to challah, viz.: If leket, shikchah, and peah, which are exempt from ma'aser, are subject to challah, then other produce, which is subject to ma'aser, how much more so should it be subject to challah! It is, therefore, written (Devarim 16:3) "bread." Just as "bread" there, is of the five species, so, "bread" here (which is subject to challah) is of the five species. (Bamidbar, Ibid.) "The first of your dough": I would understand this to include the dough of terumah and the dough of second-tithe. It is, therefore, written (Ibid.) "challah shall you separate as an offering": (The connotation is:) What is separated is holy and what remains is mundane, and not (as in the above instance) where both are holy. But they said: The dough of second-tithe in Jerusalem is subject to challah, (for second-tithe may be eaten by the owner in Jerusalem, so that it is not "holy" there). (Ibid. 21) "shall you give to the L-rd as an offering": What is the intent of this? Because it is written (20) "challah shall you separate as an offering," but we have not been apprised of the amount of the challah, it is, therefore, written "shall you give to the L-rd as an offering" — so that it comprises a "gift" to the Cohein. From here we derive: The amount of challah for a private person — one (part) out of twenty-four; for a baker; one out of forty-eight. For the dough of a private person is little, and it (less than one twenty-fourth) does not constitute a "gift" to the Cohein, whereas the dough of a baker is (relatively) large and it (one forty-eighth) constitutes a "gift" to the Cohein. R. Yehudah says: This is not the reason; but a private person is generous with his dough and a baker is sparing of his dough, and when he minimizes, he should not minimize less than one forty-eighth. From here it was ruled: A private person who makes a feast for his sons — one twenty-fourth; and a woman who bakes and sells in the marketplace — one forty-eighth. If her dough became tamei unwittingly or under constraint — one forty-eighth. If it became tamei willfully (i.e., if she deliberately made it tamei in order to give less challah), she takes one twenty-fourth (even though the challah is to be burned), so that "the sinner not profit." R. Shimon b. Yochai says: Even if it came out to one-sixtieth, it is valid, so long as there was no (original) intent (for that amount). (Ibid. 21) "throughout your generations": to include the aftergrowths of shevi'ith (the sabbatical year) as being subject to challah. For it would follow (otherwise), viz.: If other produce, which is subject to the tithe is exempt from challah, then the after-growths of shevi'ith, which are exempt from the tithe, how much more so should it be exempt from challah! — (No,) this is refuted by leket, shikchah, and peah, which, though exempt from the tithe are subject to challah. — No, this may be true of leket, shikchah, and peah, whose kind (i.e., other produce, which is not leket, etc.) is subject to the tithe — for which reason they are subject to challah, as opposed to the dough of shevi'ith, whose kind is exempt from the tithe, (ownerless produce [hefker] being exempt from the tithe) — wherefore it (the dough) should be exempt from challah. It is, therefore, written "throughout your generations," to include the aftergrowths of shevi'ith as being subject to challah. From here they ruled: If one eats of the aftergrowths of shevi'ith before its challah has been taken, he is liable to the death penalty.