Menahot, Chapter Ten, Mishnah Nine
The final mishnah of chapter ten concludes with a few more rules governing the prohibition of harvesting grain before the 16th of Nissan and a few last rules with regard to the omer.
1) One may reap on account of the saplings or in order to make a house for mourners or in order not to interrupt the bet hamidrash.
2) One may not bind them in bundles but one may leave them in small heaps.
3) The mitzvah of the omer is that it should be brought from the standing grain.
a) If this cannot be found he may bring it from the sheaves.
4) The mitvah is that it should be brought from moist (fresh) grain.
a) If this cannot be found he may bring it from dry grain.
5) The mitzvah is that it should be reaped at night.
a) If it was reaped at day it is valid.
6) And it overrides the Shabbat.
Section one: Generally, it is prohibited to harvest grain before the harvesting of the omer on the 16th of Nissan. This section provides a few exceptions to this rule, cases where the person is harvesting the grain not in order to use the grain but in order to clear the area. If he needs to make room in the field for the saplings to grow, he may clear the grain. He need not suffer the loss of the saplings, due to the prohibition of harvesting before the omer. He may also clear the grain in order to make room for either a place for mourners to gather or for sages to gather in order to study in a bet midrash. It is interesting to note that according to this source, study seems to have taken place in open fields. It is unclear whether a structure would have been built in the fields or not.
Section two: When a person is allowed to harvest grain before the omer, he may not bind the stalks into bundles as is normally done. This would make it seem like he was harvesting them for food, which is prohibited. Rather, he may leave them in small heaps on the ground and collect them later when the omer has already been harvested.
Section three: It is a mitzvah, meaning it is preferable to bring the omer from freshly harvested grain. It is preferable that on the 16th at night they should go out and harvest grain in order to bring it as the omer sacrifice. If this is impossible because there is no grain to harvest, it can be brought from already harvested grain, that has already been put into bundles.
Section four: It is best that if one bring bundles, they still be fresh (moist). However, if there are no moist bundles, he can bring the omer offering even from already dry grain.
Section five: The omer should be offered at night on the 16th of Nissan (see mishnah three), but if they wait until the day, it is still valid.
Section six: This polemical chapter ends by reminding us what we learned in the beginning of the chapterharvesting the omer overrides the Sabbath. As a reminder, non-Pharisaic sects during the Second Temple period seem to have shaped their calendar so as to avoid, as much as possible, conflicts between holidays and Shabbat. The Pharisees and later the rabbis took an opposite route and demonstratively declared that if there is such a conflict, the holiday sacrifices nearly always override the Sabbath. The editors of the Mishnah end this chapter by emphasizing exactly this pointone can harvest the omer even on Friday night.