981. Making Two Contradictory Eiruvs

Eiruvin 8:1

It is not permitted to make two eiruvs, one to the west and one to the east, in order to walk in one direction for part of the day and in the other direction for the rest of the day. It is not effective to make two eiruvs for the same day. If one did so by accident because he thought it was permitted, or if he appointed two agents to make an eiruv for him and they did so in opposite directions, he may only walk in the area where the two eiruvs overlap.

Eiruvin 8:2                                                                    

“The area where the two eiruvs overlap” means that he may only walk in the area that is common to both. For example, if one agent placed an eiruv 1,000 cubits to the east and the other placed one 500 cubits to the west, the person for whom these eiruvs were made may only walk 1,000 cubits to the west, which would be permitted to one who has the eiruv in the east, and 1,500 cubits to the east, which would be permitted to one who has the eiruv in the west. Therefore, if one placed one eiruv 2,000 cubits to the east and another eiruv 2,000 cubits to the west, he is not permitted to leave his place.