" . . . But we may not place wheat in the stones of a watermill unless it will be ground while still daylight [i.e., before Shabbat begins]." What is the reason [for this rule]? Rabba said, "because it makes a sound." Rav Yosef said to him, "Why not say that it is to extend rest to his tools!?!"
My selection this week begins with an ellipsis. Preceding this source are a range of regulations allowing passive forms of labor that begin before the commencement of Shabbat to continue throughout Shabbat. For instance, the Talmud allows us to place clothing into a solution of dye or set nets to catch fish just before Shabbat begins and then to reap the rewards of our labors after Shabbat, even though the clothes took the dye and the fish were caught (without human action) on Shabbat. Our source (most likely a second-century text from Eretz Yisra'el) presents an exception to this general rule: One may not place unmilled wheat under the stones prior to Shabbat and allow the water or wind to grind them over Shabbat. The question is why should this be prohibited, when the dye and traps are permitted.
Rabba and Rav Yosef (both early third-century Babylonian Sages) disagree as to the reason for the prohibition. Rabba contends that the mill's action would be disturbingly loud over Shabbat. Indeed, some commentators conclude that the mill's noise would leave any passerby to think that the owner is engaged in prohibited labor on Shabbat, rather than before it (as opposed to dye and nets, which both act inconspicuously). Rav Yosef, on the other hand, wonders if Shabbat prohibitions do not simply include all tools owned by Jews. Were this the case, one would be prohibited, a priori, from setting any machine or tool to perform a function on Shabbat. Fortunately, the later halakhic tradition sided with Rabba, and thus the widespread use of timers among traditionally observant Jews. That said, Rabba's exception is still alive and with us. His understanding would likely extend, in our context, to a variety of noisemaking machines, such as radios, televisions, and music players. Shabbat is a time to put away the noise of our daily lives and focus on the sounds of God's Creation.