With Succos coming very soon, it is perhaps a good idea to review some halochos of Yom Tov, in particular where they differ from Hilchos Shabbos. It is always beneficial to understand the background to practical halachos in order to have a better grasp of them.
We know that on Yom Tov we are allowed to do certain melachos in the course of food preparation. Lighting a fire to cook food is included in this leniency. We are not allowed to ’create’ a fire but we can take a fire from an existing fire to light the gas to cook the food. What about a fire for non – food purposes? The Mishna (Beitza 12a) says that Beis Hillel allow us on Yom Tov to carry a baby through a reshus horabbim to his bris or a Sefer Torah to be read in shul or a lulav where required on Succos but Beit Shammai do not allow this. The Gemara, in one of two explanations, says that the argument between Beis Hillel and Beis Shammai is whether we can apply a line of reasoning called “mitoch” (seeing that). Beis Hillel say that “seeing that carrying in the street is permitted for the purpose of food it is also permitted not for the purpose of food.” Beis Shammai disagree. Assuming the halacha is like Beis Hillel, is this only allowed for the important purposes mentioned in the Mishna or also for lesser needs? Tosfos (Kesuvos 7a) says that carrying a child in the street to enjoy a Yom Tov walk (Simchas Yom Tov) is permitted. But what if I have no need at all, like something I just happen to have in my pocket? Does my act of carrying for no reason revert to being forbidden according to the Torah or has the whole prohibition of carrying in the street on Yom Tov been cancelled? Or is it forbidden rabbinically? On this there is a further dispute. Rashi (Beitza 12a) says that it is permitted according to the Torah to carry on Yom Tov even if I have no use for what I am carrying. The Rambam agrees with Rashi. It may still, however, be forbidden rabbinically. However Tosfos (ibid) holds that if there if I have no use for the item being carried it is forbidden according to the Torah.
Are we allowed to carry something which I do not need but I am afraid that it will be stolen if I leave it; for instance a key of my house which I will not be returning to over Yom Tov. I do not need the key on Yom Tov but if I don’t lock the door and take the key with me, my house might be burgled. There is a dispute amongst the poskim about this and the Mishna Berura (518:6) says that it is correct to be stringent. However where the item is used for a mitzvah for instance a talis or lulav , the Mishna Berura (ibid) says that if a person is genuinely concerned that it will be stolen or mislaid and he only took them to shul on Yom Tov morning, he can certainly take them home even though he doesn’t need them for the rest of Yom Tov because if it were not allowed, he might not take them to shul to start with.
Is this concept of “mitoch” applicable with all of the melachos which are allowed on Yom Tov or only some of them? This is again a very controversial subject but Mishna Berura (518:) says that we say “mitoch” in connection with havara, shechita, bishul and afiah.
May we spray a wasp or fly which is annoying us? On the one hand, to kill it is a form of shechita and therefore, even though we are certainly not going to eat it, it should be allowed because of mitoch but on the other hand perhaps this is not a direct benefit similar to carrying a key to avoid a loss of money which we said before we should be stringent about. But why should it be less of a need than carrying a child on a Yom Tov tiyul for oneg Yom Tov which Tosfos (Kesuvos 7a) allowed as mentioned above?
What about lighting candles for a seudas bris? Everyone agrees that we say ‘mitoch’ with havara. The question is here is whether it is considered a need. Lighting when there is no need is called a ner shel batala which is not allowed. The poskim discuss lighting a candle on Yom Tov to show guests around your house. To light a candle because one is afraid to sleep in the dark, the Biur Halacha (514:5) allows. To light in a shul as kovod beis hakenesses is also allowed. A yaarzeit candle, the Biur Halacha (ibid) suggests lighting in shul to avoid doubt. Lighting extra Yom Tov candles by night is allowed because each candle adds extra light but during the day the Mishna Berura (ibid) does not allow it. Finally in connection with lighting candles in honour of a seudas bris, the Shaar Hatziun (514:41) is lenient because it is in honour of the mitzvah similar to lighting in a shul.
As we can see, there are many interesting questions in connection with Hilchos Yom Tov and they can be possibly be discussed in the Succa using some of the more recent sefarim on Hilchos Yom Tov. (“Do You Know Hilchos Yom Tov?” coming out next year IYH). For halocho lemaaseh, though, the final decision in any question should be made by one’s own rav.