982. Making Two Eiruvs with a Condition
Eiruvin 8:3
One is permitted to make two eiruvs in opposite directions with a condition like, “If a mitzvah or some other need arises tomorrow that requires me to walk in this direction, I will rely on this eiruv and the other is meaningless. However, if I need to go in the other direction, that eiruv is the one I will rely on and the first eiruv is meaningless.” Another condition is, “If I need to go in both directions, I may rely on whichever eiruv I choose and go in whichever direction I choose. If nothing requiring me to go in either direction occurs, neither eiruv is meaningful and I do not rely on them. In such a case, I am like any other resident of my city and I may travel 2,000 cubits in every direction from the city limits.”
Eiruvin 8:4
Just as it is prohibited to travel beyond a city's boundary on Shabbos, it is likewise prohibited to do so on yom tov and Yom Kippur. Just as one is liable for transferring an object from one type of domain to another on Shabbos, the same is true for who does so on Yom Kippur. On yom tov, however, it is permitted to transfer between the different types of domains. Accordingly, eiruvs should be made for courtyards and shittufs should be made for alleys in advance of Yom Kippur the same as they are made for Shabbos. Similarly, eiruvei techumin may be made for Yom Kippur and for yom tov as they are made for Shabbos.