R Yochanan said that according to the law of the Torah money acquires. However, because of the worry that the seller might say to the buyer your wheat was burned up in my attic the sages decreed that pulling or picking up acquire. He says the decree of pulling or picking up was to remove the possible problem of the original owner ignoring the wheat being burnt up after that it has been acquired by the buyer. The Baal Hameor says that if the wheat has been burnt up then neither can renege on the sale. The whole purpose of the law was to ensure that the owner or the buyer can nullify the deal until picking up of the object. But neither can nullify the deal unless both the money and the object still exist. I am having trouble understanding this. The sages did not want the sale to be nullified after it has been completed. Only they changed the time of completion to a later time. Why not just say which ever comes later completes the sale, either the money or the piking up of the object. So, leave the law of the Torah in its place, and say that even after acquisition by money, each can renege on the sale unless the wheat has been burnt. Also, one might ask that if the wheat has been burnt up, then the buyer is anyway at a loss, since he can not renege on the deal according to the Baal Hameor at that point (since the wheat is gone).-------------------------------------ר' יוחנן said that according to the law of the Torah, money acquires.[מעות קונות] However, because of the worry that the seller might say to the buyer, "Your wheat was burned up in my attic," the sages decreed that משיכה קונה acquire. He says the decree of pulling or picking up was to remove the possible problem of the original owner ignoring the wheat being burnt up after that it has been acquired by the buyer. The בעל המאור says that if the wheat has been burnt up then neither can renege on the sale. The whole purpose of the law was to ensure that the owner or the buyer can nullify the deal until משיכהof the object. But neither can nullify the deal unless both the money and the object still exist. I am having trouble understanding this. The sages did not want the sale to be nullified after it has been completed. Only they changed the time of completion to a later time. Why not just say which ever comes later completes the sale, either the money or the piking up of the object. So, leave the law of the תורה in its place, and say that even after acquisition by money, each can renege on the sale unless the wheat has been burnt. Also, one might ask that if the wheat has been burnt up, then the buyer is anyway at a loss, since he can not renege on the deal according to the בעל המאורat that point (since the wheat is gone). ------I asked my learning partner, David Bronson, about this type of thing where a decree of the sages can can change a law of the Torah, and he opened up the Sefer Hamitzvot of the Rambam in which there is a discussion about this type of thing.