Mishnah: . . . Nor should he read by the light of an oil lamp.
Talmud: Rabba said, "Even were it placed two floors high, and even two stories, and even ten houses one on top of the other."
The light from an oil lamp flickers when the fuel begins to run low. At this point, normally, the reader would tip the lamp to move the viscous oil to the wick in order to extend the time the lamp can burn on its first filling of oil. This act is forbidden on Shabbat. On Shabbat, the lighting of a fire, or extending, or shortening its combustion is prohibited by Torah. Reading by the light of an oil lamp is prohibited by our Sages on Shabbat, lest one tip the lamp out of habit, in a momentary mental lapse. All of this background is encoded in the Mishnah's terse statement: "Nor should he read by the light of an oil lamp."
But what if the lamp were out of reach of the reader? The reader would not be able to tip the lamp in that case, would she? Should she not be able to read by the light of a lamp under these circumstances?
Rabba's answer is no. And in this answer we find the crucial final piece of the puzzle for our understanding of Rabbinic prohibitions. Our Sages had a particular vision for the religious experience of Shabbat. Over the last few weeks we have explored that vision by delving into the nature of the types of prohibitions they instituted over and above Torah law. In order for their vision to be fully manifest, their words must have authority, in all circumstances.
May we strive to achieve their vision of Shabbat, a day of differentiated rest, a taste of the world to come.
What is our vision of Shabbat today? Does it differ from that of our Sages?
When do the needs for flexibility and authority come into conflict? How might we resolve such a conflict?