Shabbos 72 - 78
When a Little is Still A Lot
In his interpretation of a beraisa concerning the laws of borer (separating the desirable food from the undesirable) on Shabbos, Rabbi Chisda suggests that if one makes such an act of separation on an amount less than the size of a dried fig, he has done nothing wrong. His view is challenged by Rabbi Yosef, who argues that even though one is not obligated to bring a sin-offering if he involuntarily performed borer on less than that amount, it is still forbidden to do so.
Rashi explains this challenge on the basis of Rabbi Yochanan's ruling (Mesechta Yoma 74a). There, Rabbi Yochanan rules that even if one eats less than an olive size of forbidden animal fat (an olive size is the amount which would obligate him to bring a sin-offering if he ate it involuntarily) he has still violated Torah law.
Two sources are offered for this ruling. One is logic: Since this small amount has the potential to combine with another small amount to form a quantity requiring a sin offering, then it must by itself also be prohibited. The second source is the Torah's terminology forbidding "all fat" (Vayikra 7:23), indicating that even the smallest amount is forbidden.
What is Rabbi Chisda's defense against this challenge?
Two approaches are suggested by the commentaries:
Tosefos' view is that Rabbi Chisda holds that only when one separates a fig-sized amount is he considered to be doing any sort of creative labor on Shabbos, because less than that amount is considered a part of the normal process of eating which the Torah permitted.
A second approach, which Pnei Yehoshua and other later commentaries put forward, is that Rabbi Chisda understood Rabbi Yochanan's ruling to apply only to matters of eating. Even though the first of the sources for Rabbi Yochanan's ruling - the logical one, that something which can combine with another amount to create a quantity obligating a sin offering must by itself also be forbidden - would logically extend to the forbidden labor of borer, the second source, which is based on a prohibition in a case of eating, does not apply to prohibitions where eating is not involved.
Rabbi Yosef, of course, takes issue with this. He contends that even in non-food matters, there is still a prohibition even in the most minute amount.
Who Needs a Mosquito?
Whatever Hashem created in this world, declared Rabbi Yehuda, was created for a purpose. Nothing is superfluous.
This observation was directed at those who see insects and reptiles as not only of no benefit, but even as harmful.
Rabbi Yehuda, in our gemara, points out how some of these harmful creatures can be used to supply healing for damage caused to man by other creatures. Another approach suggested by the Midrash is that sometimes the harmful creatures serve the purpose of punishing the wicked who deserve the damage inflicted upon them.
The classic example is the case of the Roman Emperor Titus who defiled and destroyed the Beis Hamikdash in Jerusalem, and returned to Rome on a ship loaded with the sacred vessels he had looted from it. The gemara (Mesechta Gittin 56b) relates that when Hashem sent a giant wave to drown the ship, Titus defiantly challenged the Creator to fight him on dry land and not on the water where He had crushed Pharaoh and Sisera.
Hashem's response was that He would send the tiniest of His creatures to battle Titus on land. When Titus landed, a mosquito entered his nose and crept into his brain. It remained there for seven years, eating away at the brain of this haughty sinner and causing him the most severe pain. One of the Sages, Rabbi Pinchas ben Aruva, related that he was present when the Romans performed an autopsy on Titus after his death. In his skull they discovered that the tiny mosquito had grown into a substantial bird - a classic example of a seemingly superfluous creature carrying out its Divinely dictated mission.