Menachos - Daf 67
1. If גלגול עובד כוכבים exempts from חלה
The previous Daf quoted a machlokes Tannaim if מירוח עובדי כוכבים – smoothing of the grain piles while they are owned by idolators exempts them from maaser. Rava asked: גלגול עובד כוכבים מאי – what is the halachah about mixing of dough while it belonged to an idolator? A Mishnah teaches that the dough of a גר which he prepared before he converted is exempt from חלה. Is this Mishnah unanimous, and even those who hold מירוח of an עכו"ם does not exempt grain from maaser agree that גלגול of an עכו"ם does exempt dough from חלה (based on the respective derashos of each obligation)? Or is this Mishnah the opinion of those who hold that מירוח עכו"ם exempts grain from maaser, but those who hold it does not would derive from a gezeirah shavah (ראשית ראשית) that גלגול עכו"ם likewise does not exempt dough from חלה? Rava eventually concluded that the same machlokes applies to both.
2. The חלה obligation can be easily evaded, as opposed to maaser
The Gemara challenges Rava from two Baraisos which prove that even Tannaim who hold that מירוח עכו"ם exempts his produce from maaser agree that גלגול עכו"ם does not exempt his produce from חלה. The Gemara answers that מעשר is required מדרבנן, as a גזירה because of בעלי כיסים – wealthy people who might falsely claim they purchased large quantities of produce from idolators to avoid taking maaser. The Gemara asks why the same decree was not made regarding חלה, and answers that one can easily avoid the חלה obligation by baking less than the minimum shiur of five quarters kavs of flour plus a fraction, and the גזירה would be ineffective. The Gemara objects that one could also avoid the maaser obligation, as Rebbe Oshaya said: מערים אדם על תבואתו – a person can be cunning with his grain ומכניסה במוץ שלה – and bring it into his house in its chaff.
3. The marketplace was full of new grain immediately after the עומר was brought
The next Mishnah describes the offering of the עומר: one put the oil and לבונה into a כלי, and added the flour, poured more oil and mixed it. He then waved it and brought it near the מזבח, performed kemitzah and burned the kometz and לבונה on the מזבח. The שירים was eaten by the Kohanim in the עזרה. משקרב העומר – Once the omer was offered, permitting the new crop in consumption, יוצאין ומוצאין שוק ירושלים שהוא מלא קמח קלי – they would go out and find the marketplace of Yerushalayim filled with ordinary flour and flour of oven-dried grain from the new crop, but this was שלא ברצון חכמים – against the will of the Sages, according to Rebbe Meir, who holds the Rabbis prohibited working with the new crop before it became permitted to eat, out of a concern someone may eat it before the עומר was brought. But Rebbe Yehudah says: ברצון חכמים היו עושין – they did it in accord with the will of the Sages, and they were not concerned that someone would eat it before it was permitted.
