Rashi almost certainly never saw an olive. The same goes for other medieval authorities in Ashk’naz (Germany-Northern France). This little-known but indisputable fact has everything to do with a most important question: Is Halakhic Judaism rational and rooted in reality?
How did Rashi define the size of an olive, which is critical to Halachic Judaism? What if you have never seen an olive?
The olive tree is native to the Mediterranean basin, from Israel in the East to Spain in the west; it does not naturally grow elsewhere. In Roman times, due to the trade routes which crisscrossed the Empire, olives may have made their way to Germany and beyond. The collapse of Rome, however, led to a breakdown of law and order, and therefore trade.
Medieval Ashk’nazim were unfamiliar with olives, a fact confirmed by R. Eliezer b. Yoel’s (d. circa 1225) discussion of the minimal amount required for a b’rakha aharona: “Wherever a k’zayith is required, one needs a sizeable amount of food, because we are unfamiliar with the size of an olive…” (Ra’avya, B’rakhoth 107).
Some Ashk’nazi authorities concluded that an olive was half the volume of an egg, while others, based on Talmudic sources, understood that it must be less than one third of an egg. How much less they could not say.
The truth, of course, is different, as was clearly perceived by one 14th century authority who actually made it to Eretz Yisrael. Responding to the proposition that a person could swallow three k’zaytim at once (which is quite impossible if one assumes a k’zayit to be half of an egg in volume) he wrote: “As for me, the matter is plain, for I saw olives in Eretz Yisrael and Yerushalayim, and even six were not equal to an egg.”
S’pharadi authorities, on the other hand, had no such difficulties. One wrote that an olive is “much less” than a quarter of an egg (Rashba), while another mentions in passing that a dried fig is equal to “several olives” (Rittba). The last three statements, made by sages who saw olives, are entirely accurate.
In present day Halakhic practice, a k’zayit is often said to be 30 cc, while others say 60 cc. These figures bear no relation to the real world olives of Eretz Yisrael which average 3-5 cc. It is claimed by some that once upon a time olives were much larger. This claim is false. Olives and olive trees have not changed, as evidenced by the fact that there are over 70 olive trees in Israel ranging between 1,700-2000 years old, and 7 are approximately 3000 years old. These trees continue to produce fruit identical to the olives of younger trees.
Halakhic responsa from the G’onic period echo these facts, stating plainly that olives do not change.
The ultimate purpose of Judaism was announced by the Creator before He transmitted the Torah to His people: “And you shall be for My purpose a kingdom of priests and a holy nation” (Exodus 19:6). The nation of Israel is the priest connecting God and mankind. “I, God, have summoned you for a righteous purpose…. and have assigned you for my covenant with humanity, a light for the nations” (Isaiah 42:6).
The Jewish people, in order to succeed, have to live and lead in the real world. To deal with the challenges facing us as a nation we must think, act and believe rationally. A rational person does not believe in olives 20 times the size of the olives we see with our own eyes. To deal with reality, we have to get real.
We seem to have convinced ourselves that Halakha can be based on irrational claims and that this is not an insult to our God-given intelligence.
Nothing could be more disastrous to Judaism than its irrational practice. How can Halakhic opinions rooted in misconceptions be sacrosanct and immutable? How can we respect our Judaism if it rejects truth?
Before you eat your k’zayit of matza at this year’s seder, you might pause to consider what you are about to say about yourself, and what message you are about to send to your family and friends.
I can tell you what message I will be sending: that Torah and Halakah are as real as it gets.
Rabbi David Bar-Hayim is the head of Machon Shilo, a centre of Jewish learning in Jerusalem dedicated to the exposition and dissemination of Torat Eretz Yisrael. The teachings of Rabbi Bar-Hayim may be found at www.machonshilo.org