As we have seen, a farm worker has the right to eat while he is harvesting. A parallel halakha prohibits a farmer from muzzling his animal while that animal is threshing. This Torah law (see 25:4) is the focus of the discussion of the Gemara on today’s daf, which asks a seemingly simple question – if the animal has a stomach ailment, must we still permit it to eat, given that eating will be harmful to it?
This practical question is defined by the Gemara to mean that we must clarify whether the point of the mitzva is to benefit the animal – and in the animal’s present condition allowing it to eat would be harmful, or, perhaps, the point of the mitzva is to keep the animal from becoming frustrated that it sees food but cannot eat. The Gemara responds by quoting Rabbi Shimon bar Yoḥai who teaches that the person leading the animal can feed it karshinin, which are always good for the animal. From this the Gemara concludes that our primary interest is the animal’s well-being.
Karshinin is identified as bitter vetch or Vicia ervilia Wild, an ancient grain legume crop of the Mediterranean region, which can still be found growing in Arab villages.
Quoting Rabbi Shimon bar Yoḥai as a proof in this context is interesting, since it is well known that he is doresh ta’amah d’kra – he tries to work out the underlying reasoning behind every mitzva and apply it to the performance of the commandment – an approach that is not accepted by most of the other sages of the Mishna. The Rosh explains that the idea of doresh ta’amah d’kra is generally rejected when it negates the simple meaning of the commandment. In our case, however, it is clear that the purpose of this mitzva is to keep the animal from suffering, and we can deduce from Rabbi Shimon bar Yoḥai which type of suffering is of concern to the Torah.