Question: May one place or spray poisons against harmful insects or other pests on Shabbat?
Answer: The basis for the answer to this question depends on a related matter which we shall discuss in this Halacha. In the next Halacha, we will summarize the law regarding placing or spraying poisons against pests on Shabbat.
Allowing an Animal to Graze on Shabbat
One may allow one’s animal to graze in a place where there is grass. Although the animal is severing the blades of grass from the ground while eating, this is nevertheless completely permissible.
The Acharonim question this law based on another law brought down in the monetary law section of Shulchan Aruch:
Maran rules in Shulchan Aruch (Choshen Mishpat, Chapter 394): “One who places an animal on another’s stalk is liable to pay what the animal has damaged.” This means that if one places an animal in a position where it can eat from another’s produce, the individual must pay for the damage that the animal caused by eating.
The question is: It seems from the law regarding Shabbat that the animal’s act of detaching the blades of grass from the ground is not attributed to the person who placed it there, however, with regards to the laws of damages, we attribute the damage caused by the animal to the person who placed it there. This is quite an apparent contradiction and an explanation needs to be offered as to the distinction between the laws of Shabbat and the laws of damages.
The Poskim offer two explanations:
The Answer of the Even Ha’Ozer
The Sefer Even Ha’Ozer (Chapter 328) writes that the difference is that regarding the laws of damages, the determining factor is the “damage,” i.e. the actual result of the action. Thus, since it is clear that when an animal stands on top of grass, it will eat it, the responsibility for this action rests on the person who placed it there and he is considered the “damaging party.” Regarding Shabbat, however, the determining factor is the individual’s intent when performing the action (for the Torah only prohibits a “calculated work”). Thus, since one placing an animal on grass has no intention of performing any forbidden work and one wishes only for the stomach of the animal to be filled, one cannot be held accountable for the animal’s actions.
The Answer of the Bet Meir
The Sefer Bet Meir offers another answer and writes that regarding the laws of Shabbat, the individual is not responsible for the actions of the animal, for we do not care about the outcome of the forbidden work (that grass was detached from the ground); rather, the Torah only is only concerned that the person should not perform the work. Any work performed on its own on Shabbat without intervention on the part of the individual is not forbidden. Thus, regarding damages, the individual is held accountable for the animal’s actions while regarding the laws of Shabbat, the person is not held accountable. (It is nevertheless forbidden to perform actual forbidden works with the use of an animal on Shabbat.)
Based on the above, according to the Even Ha’Ozer, the only determining factor regarding forbidden works on Shabbat is the individual’s intention and as one does not intend for the actual work to ensue, there is no prohibition to cause one’s animal to perform the work. On the other hand, according to the Bet Meir, the determining factor regarding liability for a forbidden work on Shabbat is one’s effort and involvement in the actual work; regarding the work, however, as long as it is not being done by a person’s actions and intent, it is not forbidden on Shabbat.
Thus, according to all opinions, one may allow an animal to eat grass which is attached to the ground. In the next Halacha, we shall, G-d-willing, discuss the connection between the above law and our question regarding placing or spraying poisons against pests on Shabbat.