The Mishna on our daf teaches about the Kohen Gadol’s final preparations before the Yom Kippur service. Aside from reviewing the text of the commandments as described in the Torah (Vayikra 16), the Sages would also bring him the various types of animals that were going to be sacrificed so that he would be able to practice. They also monitored his diet on erev Yom Kippur, limiting the amount of food that he ate so that he would not become tired.
The Gemara quotes a series of baraitot that describe other limitations that were placed on his diet. Among the items that are mentioned – milk products, eggs, and wine – are things that the sages feared might bring about a seminal emission, which would make him tameh (ritually defiled) and unable to perform the avodah – the Temple service.
The Jerusalem Talmud asks why this is a concern, since the Talmud lists ten miracles that took place in the Temple during its years of operation (see Yoma 21a), and one of them was that the High Priest never became a ba’al keri (someone who experiences a seminal emission). The first answer given simply explains that, in general, we cannot rely on miracles and need to do our utmost to avoid potentially dangerous situations. The second answer given distinguishes between the first Temple, when the priests were on a high level, and the Second Temple, when they were not deserving of such miracles.
Another food that was restricted was the gargir. Eruca sativa, is an annual grass that grows to a height of 15-60 centimeters. During the Second Temple period the seeds of this plant were used in place of mustard. It grew both as a domesticated plant and in the wild throughout Israel. In several places in the Talmud it is mentioned as being a particularly good medicine for the eyes.