When walking through your friend’s orchard, would it be appropriate to pick fruits and eat them? Although our immediate reaction is that it would be forbidden to do so, the simple reading of the passages in the Torah that discuss this would seem to permit such behavior. The passages in Sefer (23:25-26) speak simply about someone who finds himself walking in his friend’s field or in his friend’s vineyard, and clearly permit him to sample the grapes or the grain. Nevertheless, the Mishna on today’s daf teaches that it is only a field worker who is allowed to eat.
According to the Gemara, the source for this is the parallel between the word tavo in these pesukim and the same word that appears regarding paying a worker (see 24:15). The Meiri suggests an additional reason, pointing out that when the pasuk talks about someone who comes into his friend’s vineyard, it sounds as though we are discussing someone who has permission to enter the vineyard, which would not be true of any passerby.
The biblical right that the worker has to eat while working is restricted to certain types of work. Thus, someone who is harvesting ripe fruit (e.g. grapes) can eat, or someone who is working with fruits that had been harvested (e.g. bundles of wheat), but are not “finished” in the sense that they have not been brought into the granary and prepared for tithing. If, however, someone is working in a field that is not yet ripe, he cannot eat from the fruit; similarly, the Torah only creates this obligation to the worker in crops that grow in the field. A farm worker who milks cows or prepares meat or cheese cannot eat from the produce, even though it is food and he is working directly with it.