IF ONE BUILDS AN UPPER ROOM ON THE TOP OF TWO HOUSES AND IN THE CASE OF VIADUCTS THE MOVEMENT OF OBJECTS UNDER THESE ON THE SABBATH IS PERMITTED; SO R. JUDAH. BUT THE SAGES FORBID THIS
The two houses are across from each other with a public space (like a road) underneath. An enclosed “upper room” – like a sky bridge – linking the two houses makes them one. Likewise a viaduct with has traffic going under the floor of the bridge is a similar link. However, according to Rabbi Judah there are virtual walls which extend all the way to the ground and allow free passage underneath both spaces. The sages disagree. Rabbah b. Abbuha even goes so far as to allow a suspended crossbeam to divide a stream of water lengthwise so that residents of two courtyards can draw water on Shabbat, by picturing an imaginary partition which divides the water in two.
A new chapter of the Mishnah begins on this page as well, starting a discussion of lost Tefillin. If they are found in the countryside where they would be exposed to the elements – what to do? Can they be carried on Shabbat? Can they be worn? Both would be problematic. Carrying can not be done on Shabbat and if Tefillin are not normally worn on Shabbat, wearing them to avoid carrying them would be akin to wearing an amulet!
IF A MAN FINDS TEFILLIN HE SHALL BRING THEM IN, ONE PAIR AT A TIME. R. GAMALIEL RULED: TWO PAIRS AT A TIME.
Now how can R. Gamaliel have them wear Tefillin two at a time?
R. Samuel son of R. Isaac replied: There is room enough on the head for laying two tefillin. This is a satisfactory explanation as regards those of the head; what explanations however, can be given in respect of those of the hand? — The same as that which R. Huna gave, for R. Huna explained: Sometimes a man comes from the field with his bundle on his head when he removes them from his head and binds them on his arm.
Which leads us to the consideration of how Tefillin are to be worn – that is, what does it mean to “wear” them.
It was taught at the school of Manasseh: Upon thy hand,(Deut. 6:8) refers to the biceps muscle: between thine eyes,(ibid) refers to the vertex. Where is this? — At the school of R. Jannai it was stated: on the place where a child's brain pulsates.
Location, location! And if the location is specific, its hard to see how two can be worn at once.