We are beginning Klal 3, which deals with the cleanliness aspect of a person’s Torah and tefillah. We will also learn Klal 4, which deals with a person’s body parts being properly covered for davening. We will begin with an introduction.
In Parshas Ki Seitzei (Devarim 23:10), the Torah tells us that when Klal Yisroel goes out to war, the encampment must not have any davar ra. The first element the pasuk discusses is tumah. Next, the Torah tells us that Klal Yisroel must have a place outside of the camp for relieving themselves. The pasuk explains that every soldier should have a shovel among their weaponry, so that when they relieve themselves, they can cover up the waste. The Torah explains that Hashem travels with Klal Yisroel when they go to war, so the camp should be kadosh. Furthermore, the pasuk adds that Hashem should not see ervas davar in the camp, for otherwise Hashem will leave the camp.
We see that there is a mitzvas asei of vehaya machanecha kadosh, and a lo saasei of velo yireh becha ervas davar. The asei is learned from when the pasuk says that there should not be uncleanliness in the camp, and if there is, that it should be covered. The lo saasei is learned from the example of not allowing ervas davar to be visible. From the fact that the Torah applies this halacha when going to war, which is a time that Klal Yisrael brings the shechina into their camp (through their learning and davening), we extrapolate to all similar cases.. Thus, any time one is learning or davening, these mitzvos apply.
Thus, we see that the Torah gives us an asei and lo saasei to maintain proper decorum in the camp. Chazal understand that these are dinim deorasya, and that a person cannot daven or say divrei torah in the presence of tzoah, human waste, or ervah, the human body which is uncovered.
The Chayei Adam will add that this issur also includes when the tzoah is covered but remains on the person’s body, such as that they did not clean themselves properly, or when a person needs to use the facilities.
We are not going to learn every single siman of these Klalim, but we will cover both topics thoroughly, be’ezras Hashem. We will also learn the Mishnah Berurah’s introduction to these halachos. The introduction to tzoah in the Mishnah Berurah is in siman 79, and the introduction to ervah is in siman 73. In the Shulchan Aruch, the halachos are spread throughout various simanim, but in the Chayei Adam, the halachos of tzoah are in siman 3, and the halachos of ervah are in siman 4.
The Torah gives us a mitzvas asei to remove tzoah and lo saasei against ervah in order to maintian proper decorum in our camps.