Much as the oil had to be brought from the finest ingredients, similarly the wine for the libations also needed to be of the highest quality. The Mishnah on today’s daf (=page) includes information about where the grapes for this wine were, ideally, harvested, how they were to be grown, and how the wine was to be produced and stored. Finally, the Mishnah teaches that the libation wine should not come from the top of the barrel, where there was “flour” (white dust that was produced during the fermentation process) nor from the bottom of the barrel where the sediment settled, but only from the middle. In order to assure this, the appointed official would sit next to the barrel of wine with a stick in his hand as it was being poured. As soon as he saw that there was refuse being poured out with the wine, he would bang on the barrel with his stick indicating that no more wine should be drawn from this barrel.
The Gemara discusses this situation and asks why the official needed to bang on the barrel. Would it not have been simpler for him to shout out his instructions? In response the Gemara quotes the teaching of Rabbi Yohanan who said that although speech was good for preparing the incense, it was bad for the preparation of wine.
Many explanations have been suggested to explain Rabbi Yohanan’s teaching. According to some, the sound waves produced by speech help the mixing process of preparing the ingredients for the incense; others say that a metered sing-song or recitation allowed the workers to work at an even pace. One further explanation is that large volumes of ingredients were worked on at one time, so there were two workers grasping the mortar together and it was essential that they worked in tandem. Speech was what allowed them to do that. According to these last approaches, rather than saying that speech was good for the incense, the statement should be understood as teaching that the sound of their voices was good for the people working at preparing the incense.
Tosafot point out that there is a parallel statement that appears in Masechet Keritot (daf 6b) where Rabbi Yohanan suggests that the workers should chant together “pound well, well pound!” as they work with the mortar, since that is good for the incense – even though it is bad for wine.