New York – ‘Kzayit’: Torah, As Real As It Gets


    New York – 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 should matter to you. It has everything to do with the following question: Is Halakhic Judaism rational and rooted in reality, or is it a hypothetical construct unconducive to engaging the real world?

    It is a simple matter to ascertain, or describe to another, the volume of an average olive, a ‘k’zayit’…provided you have olives. But what if you have never seen an olive? How would you understand the concept? How would you describe it to someone unfamiliar with olives?

    This was the reality in Ashk’naz in the Middle Ages, and there is no mystery as to why. 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 demonstrated, based on Talmudic sources, 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, predicated on opinions rooted in the aforementioned lack of knowledge and experience, 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. Some would have you believe that there are two kinds of olives: real olives and ‘Halakhic’ olives. In their view, Halakha need not reflect reality; it exists in an alternate reality of its own. This is a tragedy because it paints Judaism as divorced from reality and irrelevant to a rational person. This is a lie because Torah was intended by Hashem as our handbook for operating in the real world.

    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 2o times the size of the olives we see with our own eyes. To deal with reality, we have to get real.

    We are described as being created in the image of Hashem because we can think and reason. To convince ourselves that Halakha can be based on irrational claims is an insult to our God-given intelligence. Not to mention that it places Judaism squarely in the realm of fairy tales. What kind of message does that send to our children?

    Nothing could be more pernicious than the notion that truth and Torah do not mix. The same goes for the idea that Halakhic opinions rooted in Exile-induced misconceptions are sacrosanct and immutable. A philosophy that turns aberration into truth, the Torah of Galuth into the real McCoy, is intolerable. The clear implication is that Judaism, as a system, is broken and beyond repair.

    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.

    David Bar-Hayim is an Israeli rabbi who heads the Machon Shilo Institute in Jerusalem, Israel. HaRav Bar-Hayim’s beth din is well-known for having issued a p’sak halakha permitting the consumption of kitniyot for all Jews residing in Eretz Yisrael.

    In 2009 VIN News had an exclusive interview with Rav Bar Hayim.

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    1. I’m glad that this issue is being publicized. Kol Hakavod to R’ Bar-Haym for being a voice of reason in a world where the only way to be more frum is to be more machmir. R’ Natan Slifkin brought up this issue a few years ago, and has a long article on it, for those interested in further sources on the topic.

    2. Kol ha kavod for the intention, but the trouble is that in order to overrule an halachic ruling of previous generations, even an erroneous one like kitnyos, or a shiur like k’zayit, one must be on a level greater than those who instituted it. Otherwise, the dishonor to our forefathers is not outweighed. Even the Lubavicher Rebbe, ZTK”L, who checked the pots on Pesach to ensure that the Sephardim had rice to eat, was not so bold as to cancel the ban on kitnyos or do a new, scientific measurement of a k’zayit. There is simply more to Torah than our secular understanding of the world.

      • One does not have to be a “gadol” to decide that certain arcane halachos that were clearly based on temporal circumstances (i.e. unique to the time the halacha was adopted) and not based on some principle that transcended the circumstances of the moment could be modified or changed as those circumstances changed. Its no “insult” to our forefathers to change our l’vush to reflect the fact we now live in Miami where the year-round temperature doesn’t require a fur hat and heavy black coat or change the foods we serve for shabbos because we know that tofu and green vegetables are much healthier than fatty red meat and potatoes. Times change and minhagim and halachos that were time/location-specific also can change w/o having to “consult” a gadol. Some things are intuitive, some are not.

    3. Surely the reason that Chazal used measurements related to everyday objects, rather than use the measuring terms of their eras and areas, is that these would remain viable in all era and locations. Volumes like a Beitza, a Zayis and Melo Lugmov are obvious. If you have never seen an egg or an olive, by all means err on the side of caution, but if you have, you know how much you are required to eat. Yasher Koach.

    4. Truth is not always what we see in front of us.

      The Rambam lived in the Middle-east, including a short time in the land of Israel, so I am rather sure he saw some olives. The Rambam, on the second Mishnah in Eduyot, says that K’Zayit is 9 dirham. A dirham is 3 to 3.2 grams. Hence a K’Zayit according to the Rambam is 27 to 28.8 grams.

      This Rabbi has an agenda and is ignoring other opinions.

      • Michael: Rambam there says nothing about a K’zayis. He talks about OTHER measurements. And just because you know what a Beitza is has no bearing on the size of a Zayis. See Rabbi Slifkin’s article, the Evolution of the Olive for more information.

        • I quoted a source from the Rambam. It’s toward the end of the Rambam’s long comment there. Feel free to look it up.

          I have read (much of) Rabbi Slifkin’s long article, and I found it disingenuous when he wrote “Furthermore, from the fact that Rambam does not specify the size of a kezayis – whereas he does specify the size of other quantities – one can presumably infer that his position was that a kezayis is the size of an ordinary olive…”

          The Rambam does give a measurement for a K’Zayit. He gives it in dirham, which is a weight measurement, not a volume measurement.

        • The Rambam expressly states that if a kezayis of issur falls into three beitzim of hetter, then that is considered “taamo u mamasho” and one is chayyav malkus for eating that.

          It is commonly assumed by poskim that the Rambam holds that an olive is one third the size of an egg. That means that you have one measure of issur for nine of hetter, or roughly 1/10. That does seem to be about the amount you would need for mamasho. (The other view, Rashi, has an olive 1/2 the size of an egg and uses four eggs for a pras, not three. So instead of 1:9 you have 1:8. The two shiurim are not that far apart at all. The Rambam’s taamo u mamasho is 10% issur, Rashi’s 11%.)

          If you hold that an egg is only 3 cc (as does teh article), three eggs, even using Medium eggs, are 43 cc X 3 = 129 cc. That is already close to being battel be shishim — and in no way could that be called taamo u mamashoh.

          • Explaining Avoda Zara 67, Rashi learns that mamasho means that the issur is whole, not dissolved. The Rambam (Maachalos Assuros 15:1-3) disagrees, learning that mamasho refers to a complete shiur of issur — a k’zayis, even if dissolved. Taamo without mamasho would mean that less than a k’zayis flavored the mixture. Taamo u mamasho means that both are present, shiur and taam. That it’s “close” to bittul is irrelevant. I’m not sure why you feel a need to attempt to make Rashi and the Rambam dovetail when they clearly disagree.

            Of course, having highly technical shakla v’tarya on a blog is kind of funny.

            Michael in Seattle:I thought you must have a Rambam with more in it, and I was going to look up what R’ Kapach has! Thanks for saving me the effort. I appreciate your honesty.

      • What you are saying is not exactly correct.

        3.2 grams was the weight of the Dirham during the Ottoman regime in Eretz Israel, but, according to some scholars, in the time of the Rambam it was about 2.8 grams.

        Therefore, the Rambam’s Revi’is is 75 grams, which is 2.64 ounces.

        • Shlomo2 ,

          Thank you for that information. I did not know that a dirham may be as little as 2.8 grams.

          It still comes out that according the the Rambam a K’zayit is between 25.2 and 28.8 grams.

    5. R’ Chaim Volozin also held that a K’zayis was just that — the size of a contemporary olive. Rav Hadar Margolin once told me that he asked R’ Shlomo Zalman Aurbach Z”TL if one could rely on this for achilas matza b’shaas hadechak. R’ Shlomo Zalman replied something to the effect of, “Why only b’shaas hadechak?”

    6. According to what I learned in Chedder, (according to many Posskim) the dispute over the size of an olive, or an egg for that matter, has resulted simply because “Nishtaneh Hatevah”. The Torah measurements are based on sizes common in Biblical times. But “nature has altered”. (Usually it has diminished.) Therefore we aren’t clear about a “Kzayit”, even though we see plenty of them. (There’s also, I think, different opinions regarding “size versus density”.)
      BTW, I personally don’t believe that Rashi never saw an olive. He traveled extensively and I’m sure he either came across some (imported, pickled) olives, or spoke to reliable people that were familiar with olives.
      Rashi is particularly famous for his integrity. There are numerous places where he states clearly “I do not know”. If his (or other Rishonim’s) measurements where “guesswork”, he (and they) would have mentioned it.

      • “Nishtaneh Hatevah” is a cop-out used by those who can’t believe that Chazal might have been wrong about reality. It should have no place in Halacha. Just like you can’t believe that Rashi never saw an olive, I can’t believe that he would give a Shiur that is and was clearly wrong in his time and NOT mention that in Chazal’s time olives were bigger.

      • Read the article. There are olive trees currently in Israel which have been producing fruit for 2000, even 3000 years. The fruit are identical to those today.

        We have all manner of animal skeletons, preserved plants and human remains from those times. We even have beans and grain which have been grown out like the Anasazi bean. They are the the same size now as they were then.

    7. Chazal say that the land has been cursed since the destruction of the Bais Ha Mikdash. The Torah itself tells us that when the meraglim returned from surveying the land, it took several men to carry one grape vine due to the huge size of the grapes. If anyone has any question of the veracity of this story, take a look at a Temani esrog (the size of a football) and compare its size to the other common varieties (size of a baseball). This story is based on false premises.

      • That’s not what the pasuk in Shelach says. It says that the branch with a cluster of grapes was carried on a pole between two (people). Inferences about the size of an individual grape are just that — inferences. And if olives were of an unusual size, why didn’t they take some of those too?

        • Because the Meraglim were in the summer. Figs, grapes and rimonim start bearing fruit in the summer. Olives are picked long after Succos.
          That’s why the Meraglim couldn’t bring back olives. They couldn’t find any.
          (BTW the reason they didn’t return with dates which do ripen in the summer is because Moshe told them to only explore the mountainous region. Dates grow in lowlying areas)

      • “The Torah itself tells us that when the meraglim returned from surveying the land, it took several men to carry one grape vine due to the huge size of the grapes. ” No, it doesn’t. It says that the grape CLUSTER was huge. It doesn’t say anything at all about the size of the individual grapes.

    8. Rav Chaim of Volozhin and the Avnei Nezer maintained halachah l’maaseh that the kezayis is the size of an ordinary olive. Even the Chazon Ish acknowledged that me’ikkar hadin this is the correct position, and everything else is chumra.

      • I don’t know about the Chazon Ish, but it is rather the Noda BeYahuda who’s the author of the Chumra “Niskatnu Hashiyurim”. Most disagreed with him , even his talmid in Teshuva Mehavah is skeptical about this chumra.

        BTW, Its worthy to note, according to the author R Bar Hayim, refraining from any Kitniyoth eating on Pesach is nothing but an error…if you really looking for his controversial P’sakim…

    9. My recollection of Engine. Translation of The Alschich on Beraishis is that when Moshiach comes, the natural order of the world as it was before the tree “misrep” will return and we will be harvesting finished bread, not wheat. We also know from the reports of the spies that produce size is relative to Hashem’s motives at any given time. So, we really don’t know how nigh olives were when he had the Bais Hamikdash or the presence of eminent scholars and their mates. Am I missing something here?

    10. GEVALD!!! This so-called rabbi would not reach the toe-nail of one of our heilige rabbunim. He is telling us to look at reality! What does reality have to do with anything? We care only about the emes as taught to us by our heilige rabbunim. If the rabbunim say that a kezayis is the size of a watermelon, then that is the emes, and the reality does not matter.

      Now, he’s attacking the shiur of a kezayis. Next, he will say that metzitzah bepeh is just a minhag that has no health benefits. Next, he will say that saying perek shirah does not work for shiduchim. Soon none of our sacred superstitions will be left. GEVALD!!!

      • I don’t know about the “Right Wing” part of your posting name but the “Lunatic” portion is clearly on point. The last time I read somthing so absurd were in comments by a Christian Evangelical Preacher who sounded like the founding member of the Flat Earth Society. What you call “emes” as taught by some “heilege rabbunim” in the medeval ages was probably somthing they believed to be truthful and accurate a thousand years ago. However, times change and knowledge changes and we are not a bunch of mindless robots who march over the cliff because some “heilege rav” in the 12th century thought the earth was flat or that it was OK to do a lot of stupid things we now understand are threats to our health and well-being.

        • #13’s contribution was written with a large dollop of humor and perhaps even sarcasm – all of which has clearly evaded your intellect.

          Clearly, anonymous #22, you left your sense of humor in your locker last time you visited the mikveh.

      • Your thinking is both dangerous and scary.

        Many things change as time goes on. Rational people recognize that poskim of the past relied on the knowledge of the day. Think of medical science, for crying out loud.

        It is OK for us to take what we knew then, combined with a psak halocho from the day, and then contrast it with what we know now to ensure that we are correct.

        The process of deciding halacha is fluid. We are constantly learning things about the world that challenge our conventional thinking.

        I am certainly not saying that we should just throw away our messora or dismiss the emes we learned from gedolim of the past. That would be stupid and an afront to H” and his Torah. However, it is just as stupid do ignore, dismiss or deny reality. H” allows us to learn, to evolve, and to understand more and more as time goes on. We know and understand so much more today than even the last generation did.

        Again, I’m not saying we should all start eating less matzo by the seder. But, the argument is certainly valid, and it should be important to all of us to rationally separate halacha from minhag or messorah.

        • Both you and another (upstream) poster are taking “RWL”‘s post (#13) at face value, and the reaction of y’all (Since you’re some kind of Southerner) has been identical. (Riled up about the (seeming) irrationality of the post. What you (y’all, again.) fail to realize is, that the tone has been sarcastic, written by an incurable cynic. I stopped taking him/her at face value towards the end of the first paragraph.

      • “…What does reality have to do with anything? We care only about the emes as taught to us by our heilige rabbunim. If the rabbunim say that a kezayis is the size of a watermelon, then that is the emes, and the reality does not matter…”

        This is by far the most ridiculous thing I have ever heard come out of a frum person’s mouth (or keyboard.)

      • To: Right_Wing_Lunatic,
        So what you’re saying is if your rebbi tells you that being intimate with your spouse is assur (kitzur shulchan aruch) you’d believe it to be “emes”? Even though the Ram am states otherwise? There are 70you explanations to Torah. Back in the times of the Talmud many rabbis had different opinions yet they loved and respected one another.
        Also, for the record, Metzitzah bePeh is a minhag that MUST BE STOPPED! To date it killed 2 babies (that I personally know of) because the Mohel transferred HERPES to the infants during that act…
        Have a Chag Kasher V’Sameach and a refuah sheleima.

        • I’m really sorry that I upset you so much. I did it only for laughs. See my second comment (#34).

          I fully agree with you about MbP.

          (But, just out of curiosity, where is the Kitzur Shulchan Aruch to which you refer?)

          Many thanks for your wishes for a Chag Kasher V’Sameach. May the one who blesses be blessed.

          • Amen bro! The source for my reference above is in Kitzur Shulchan Aruch (Rabbi Shlomo Gantzfried) Siman 150, Halacha 9: “And even when he is with her, he should not intend to enjoy…”. Where the Rambam writes the exact opposite in Sefer Kedusha, Hilchot Issurei Biah Perek 21, Halacha 9: “A man’s wife is permitted to him. Therefore a man may do whatever he desires with his wife. etc”
            For more see:
            I’m not affiliated at all with Chabad, but their site offers the best English translation to the Misneh Torah.


    11. “It is claimed by some that once upon a time olives were much larger. This claim is false.” So what about the medrashim we are all familiar with regarding the fruits of eretz yisroel in the time of Moshe being carried by multiple people, like the famous picture of grape vines on the shoulders of four carriers?

    12. Also found this on a website:

      1 extra large (XL) egg – with a wegight greater than 2.25 oz (64g) will yield 4 Tbs (about 56 ml)
      1 large (L) egg – with a weight greater than 2 oz (57g) will yield 3 Tbs + 1 tsp (about 46 ml)
      1 medium (M) egg – with a weight greater than 1.75 oz (50g) will yield 4 Tbs (about 43 ml)

      • I suggest you open up the first Mishna in Horayot. Or for that matter the gemara in Yevamot 92a “horu bet din [and here we’re referring to the BD of 72 in the Lishkat haGazit of the Beit Hamikdash, not Rabbi Murray or Rabbi Irving] she’shak’a chama u’l’vasof zarcha chama EIN ZO HORA’AH ELAH **TA’UT**”. [see the psak of the Rambam in Hilchot Shegagot 14:3]. And while you’re at it, open up a Shulchan Aruch Choshen Mishpat to Siman 25 “Dayan she’ta’ah matai chozer u’matai meshalem” and check the Nosei Keylim. I recommend the Sefer Aruch haShulchan CM 25 for a great summary of Rishonim and Acharonim.

    13. I am sorry that I made a mistake.

      I looked at the Rambam that I quoted above, and he does not say what I thought he said. He comments on a Revi’is only, and I read elsewhere about using that amount to calculate a Kezayit. I confused a later Rabbi’s commentary with being the Rambam’s own words. The Rambam does not directly address a Kezayit there.

      • Michael:
        The Rambam, like other Rishonim living in places where olives were common, never defines the size of an olive. One can presume that this is because, for them, an olive is an olive. Period. The olive hanging on the olive tree outside, or the one on your plate, is what the size of an olive is.

        Even if you want to calculate it, which Rambam did not do, you can use the revi’is as your starting point.

        Rambam’s revi’is is no more than 2.65 ounces.
        A revi’is is 1 1/2 eggs.
        At least three olives per egg.
        At least 5 olives per revi’is.

    14. Read the article. There are olive trees currently in Israel which have been producing fruit for 2000, even 3000 years. The fruit are identical to those today.

      What’s the basis for saying they are the same? Ever heard of bad harvests?

        • “… Hamotzi mechavero alav ha-ra’ayah …”
          In your haste to display your erudition, you’ve done the exact opposite.
          A little bit of knowledge is dangerous!

          This rule is invoked in Dinei Momoinois, not, in Shiurim for Mitzvois.
          Maybe, you should go learn a Yeshivishe Masechtoh, preferably in N’zikin.

    15. To commenters 22,27, and 29.
      I agree with 22 and 27. What I wrote is indeed lunacy (27), as well as dangerous and scary (27). However, I disagree with 29. This cannot be the “must ridiculous thing” that you have ever heard from a frum person. Lots of frum people actually believe and espouse this type of nonsense.

      I suggest that you all look up “Poe’s Law” on Wikipedia. Briefly, it states that one cannot tell the difference between satire of religious (or other) extremism and the real thing because they are both equally insane.

      BTW, I left a few clues that you missed. a) I called myself “Right_Wing_Lunatic.” b) I referred to shiur kezayis, MbP, and reciting Perek Shirah as “superstitions”. c) I wrote in correct English.

      • I wrote a nice retort to your original piece (#13), where I caught on early to your sarcasm. Unfortunately, (Or, perhaps fortunately) the editors at VIN did not put it up, as they do with 70% of my posts where they feel that it gets too personal, sometimes. One day, (hopefully), I’ll publish a book of all my posts that didn’t make it to the air. It will (probably) climb the charts faster than that rotten egg Sarah’le Berkovic, a/k/a Deborah Feldman’s “Memoir”.

          • Adaraba, what?! Just like Amazon, I’ll let you read some excerpts. There is one Choshuve poster (who shall remain nameless) who thinks he/she is a great Torah scholar, linguist, Historian and humorist, who has a habit of riling up the other posters/readers with ridiculous statements, especially where religious belief is concerned. As a retort, I profile that person in a humorous (but respectful) way. The powers that be at the VIN editorial desk (or couch), however, feel that the post is not suitable to go on air. So it ends up on the floor of the cutting room, thus depriving the audience of some good natured, stinging humor.

      • You are the best!!!!! Great comedy writing! Hard to believe that people thought you were serious, but, as you said .Poe’s Law …

        Anyway, the article sounds correct in every respect, except for one thing. The danger is that although in this case, clearly, the kzayis has been greatly exaggerated, one might generalize from this to many other areas in which cone could make very rational arguments, based on “reality”, that what Chazal said is outmoded, now discovered to be incorrect , etc., when the subtleties are not as easily discernible. We therefore have no choice but to follow the majority of poskim who alone have the power to change accepted norms. Even they have no such power in many cases, which is, to my mind, one of the main reasons that we need Moshiach to come – to help re-establish a Sanhedrin who could really look at many modern dilemmas with unquestioned authority.

        I heard Rav Berel Wein say once that there are in fact several things that we have from the past that need updating and cleaning up. But the problem with change is that people tend to throw out the baby with the bathwater.

        Looking forward to chugging down that major k-zayis . . .

    16. Michael:

      To add to what i wrote above:
      Of course, there is no reason to believe that Rambam would define the size of an olive as anything other than the olives he saw. Therefore, even the calculation I was making above, is not consistent with the Rambam, whose olive would be significantly smaller even than what teh calculation yields.

    17. For some reason, one of my posts has gone missing. I pointed out that both olives and eggs have a wide variety of sizes. See these websites;

      The largest eggs are twice the size of the smallest, and the largest olives are almost FOUR TIMES the size of the smallest.

      Go to any shuk or gourmet market, and you will see a variety of olives of different sizes being sold. The largest are indeed roughly 1/3 to 1/2 the size of a medium egg.

      • For one, the gemara knew of large olives and wants us to use a regular sized olive, not a giant one.

        For two, it’s important to note that, while olives have not grown in size, eggs have. This is because we have been breeding and selecting chickens for larger and larger eggs over thousands of their generations. As a result, you could not safely hold 2 eggs in your throat (even the smaller ones) like the gemara states. If you had a medium egg from chazals time, a normal sized olive would certainly match up with the measurements of the rishonim.

        What R’ Ben Hayyim is saying is that it’s all irrelevent because chazal wanted us to use the olive/egg measurement we see before us, not the size it was in chazals time or biblical or what have you. This is also the opinion of the Geonim.

    18. Rabbi Bar-Hayim writes: “We are described as being created in the image of Hashem because we can think and reason. To convince ourselves that Halakha can be based on irrational claims is an insult to our God-given intelligence. Not to mention that it places Judaism squarely in the realm of fairy tales.”

      So true

      • Every historical meteorologist worth his salt disagrees with you. But what good will that do if Torah itself disagrees with you and you do not care. Keep blogging and being machti es harabim instead of learning…..

    19. Now, that we know that the world has many time-zones, should American Jews still keep the Zman of Hachnosas Shabos, seven hours after HKB”H started keeping His Shabos in E”Y?
      Now, that we know that the moon doesn’t really light up anew, on Rosh Chodesh, its only caused by the angle towards the Sun, should we still be Mchadesh the Levonoh?

    20. I am very surprised that VIN should post something from the Shilo Institute. Under the guise of scietific-style analysis they are attempting to create a new Torah. They may have brilliant minds; they may have studied much Torah. But they have no connection to the Torah as passed from generation to generation as described by the Rambam at the very beginning of his Commentary to the Mishnah. That is the starting point of everything we do, and this is something to which they have no connection.
      With regard to the claim that olive sizes have not changed, People who have at least a passing knowledge of the modern world should not be aware that the speed of light has been changed by scientists several times this century – not just as a refinement of the calculations, but actual revisions that were each time supported by evidence from labs, until the next revision, when evidence again came in to support it. If the speed of light can change, anything can change, and the fact that olives today growing on 2000 year old trees are the same size as those of much younger trees means nothing. Sizes can change universally with climate change and many other other factors.

      • What are you talking about? Rav Bar Hayim and his colleagues reinforce what our rishonim tried so hard to teach us as opposed to some of our achronim’s teaching… Rav Bar Hayim has been my rav for 12 yrs. My love andit understanding of Torah has only enrichen since.

        • Do I have to be more explicit? They are Conservatives that speak Hebrew.

          Wikipedia: Rabbi Bar-Hayim was born David Mandel 24 February 1960 in Sydney, Australia. He studied at the Merkaz Harav Kook yeshiva in Jerusalem for 10 years.

          I understand, though, where you are coming from: If you have never learned anything other than what they taught you, of course you appreciate them. But their scholarship – however analytic and scientific – does not fit with the system described by the Rambam that I quoted. Those of us who adhere to the traditional rebbi-talmid school of Judaism (commonly known as Rabbinic Judaism, or Pharisees to others) cannot and will not accept that approach. I personally enjoy the scientific analysis of questions such as this, but it has nothing to do with halacha l’maaseh. Mandel aka bar-Hayim is trying to mix two worlds and comes down in favour of the scientific one. That is exactly what the Sadduccees did in their day: They mixed Greek thought with Judaism and gave preference to the Greek, arguing that it had a stronger philosophical/scientific basis.

          • So what you’re saying is there is only one panim L’Torah – But not seventy….?
            I learned in Yeshiva Chaim Berlin (Litvak Yeshiva) for 7 years. I was not allowed to question any of my rabbeim (I was very respectful to them, yet the dismissed my questioning and some even belittled me infront of my classmates). Rav bar Hayim always gave me solid halachic (not scientific) answers regarding many questions, and always showed me the their sources (In Tanach, Talmud, Rambam and Shulchan Aruch). He is a very learned man, and I have the upmost respect for him. You are welcome to disagree with RBH, but to belittle him, simply because you do not agree with his opinion is simply wrong and immature. Isn’t that the reason the second Beis Hamikdash was destroyed? You forget that in the time of the Talmud, many Rabbis disagreed with one another, but they still had love and respect to one another. They were true Rabbis. Today, it’s the oposite….If one rabbi does not follow the “Stream”, he will be labled an outcast, and boycotted…. What happened to the love and respect towards one another, are we Jews or simpletons… What happened to shivim panim l’Torah….?

            Chag Kasher Sameach 🙂

            • This has got nothing to do with 70 panim l’Torah. This involves someone who simply does not have a mesorah and presumes to reach his own decisions in an attempt to transform traditional Judaism. I can see from your posts that you are a serious person, but with respect you simply have not grasped this point. I would suggest that it is because you have swallowed Mandel aka bar-hayim’s philosophy hook line and sinker.
              I don’t have a knowledge of Chaim Berlin Yeshivah or its rebbes, and even less of what sort of questions you might have asked them, but I have heard your complaint many times from ex-talmidim of Litvish yeshivas. Interestingly though I have never heard this complaint from hasidish yeshivas (and that’s not they don’t ask!). Perhpas because the Litvish world traditionally invested so much effort in ‘only gemara’, they have ignored everything else, with the result that their perspective is extremely blinkered and has taken a much more extremist and fundamentalist approach to life, with the result that questions – particularly rational(ist) pose a direct threat to their mindset.

          • I agree with you regarding R Ben Hayim, I have read quite a few of his P’sakim and all I can say, he may be brilliant, but he is dead on wrong on many issues. He will go against classic p’sak and tradition,without any problem,and all will be based upon some sources and questions,on which he persumes as he himself has disovered, while most issues and questions have been at the hand of the Achronim and are clearly disussed, and despite that ruled differently. He might find a few rishonim agreeing with him, but that is not how to approach p’sak halakha. You can not start disputing every traditional p’sak by digging up new rishonim, etc.

            • Digging up “new” rishonim? Do you even listen to what you are saying? First of all Rishonim aren’t “new”. Their psak halacha came before the psaks of achronim. Let me ask you this: If achronim can argue with rishonim, who happened to have a bit more knowledge than todays rabbeim, who says a Rabbi today cannot reinforce opinions by well respected rishonim (Rambam, Rosh, Rif, etc)?
              Where is this “rule” that one cannot, comes from?

            • ” Digging up “new” rishonim?

              What I was referring to is recently discovered Rishonim, yes, if it would to be the Rishonim like the Rif, Rosh…

              Correct, Achronim can NOT “argue” on Rishonim, however, Achronim like the RM”A Sulkhan Aruch, Magen Avrohom based their opinion upon on Rishonim they had on hand, and so was tradition based upon those. And those are the Rishnim we base our final P’sak.
              Therefore, you can NOT go against all tradition by finding others and disputing all, it is one thing if you want to be “Machmr” however, you can not officially rule leKulah against traditional P’sak.

              (I will give you one logical reason, you do not know ALL rishonim they had at hand, all you know is what we have nowadays, and that is what you are comparing it with. They might have had many other rishonim siding with their opinion which they didn’t quote, and thus you are missing the big picture.
              It is simple, you can never go wrong by just following those traditional ones, but if you decide differently –you better be dead-on right!

    21. To anyone who thought that my first comment (#13) was off the wall, read the following REAL quote from a speech by Rabbi Uren Reich (Rosh Yeshiva of Woodlake Yeshivah in Lakewood)

      “If the Gemara tells us a metzi’us, it’s emes veyatziv. There’s nothing to think about. Anything we see with our eyes is less of a reality than something we see in the Gemara. That’s the emunah that a yid has to have … We’re coming to hear new kinds of concepts, that we have to figure out a way to make Torah compatible with modern day science – it’s an emunah mezuyefes!”

      This was said by a Rosh Yeshivah in a speech at an Agudah convention! Can’t get more mainstream than that. It makes me want to cry.

      • The only problem with this approach is that one may perhaps – just perhaps – not understand exactly what the Gemoro is getting at, even if one is a BIG rosh yeshivah. Mindsets change and what were givens at one time cease to be generations later. The basis of what the RY said is itself not unreasonable – it’s just that he presumes to be the arbiter of its explanation, and that is very dangerous.

      • Yeah. But there is a huge difference between your post (#13) and the speech of the Rosh Yeshiva. In the spirit that it was given/posted. The R”Y made that statement in order to point out the fact that whenever it is unclear whether the determinations of Chaza”l are compatible with what we know as today’s reality, we should assume that Chaza”l had it right and we have to work harder to understand their statements and determinations. Your (original) post, on the other hand was written in a “Tongue-in-cheek” spirit, juxtaposing the seemingly (Or factually) ridiculous “Superstitions” with real life.

        • I respectfully disagree. I think that the RY was arguing against your very point. He was saying that one should NOT try to make the Torah compatible with science. Rather, we must accept the straightforward meaning of the Gemara at face value. Any scientific conclusions that fit with the pashtus haGemara may be accepted; all those that run counter to the pashtus haGemara should be rejected.

          This is a mainstream opinion in the Yeshiva world (not to mention the Chasidim). I have heard it espoused many times. Sad but true.

    22. There is a scientific principle that from my studies and experience is sacrosanct, and if it is questioned, one become subject to ridicule and derision: Uniformitarianism. The scientific BELIEF that the laws of nature behave in precisely the same way, at all times, and in all locations. The Jewish People are privy to knowledge of another force which overrides Uniformitarianism, which precedes it, and which is the basis of creation of something from nothing. Only cosmology comes close to contradicting Uniformitarianism, when it explores the fractional moments after the instant of creation. Be sure, one day, this knowledge will be commonplace and rest assured that every word of the Torah will be understood as Truth by everyone. Don’t put too much faith in Uniformitarianism and don’t make the logical error of applying it to Halacha.

      • This statement is quite misleading. That the laws of nature behave the same is in fact a testable hypothesis, and you can believe that every scientist in the would would love to prove that they don’t because it would result in worldwide fame and an immediate Nobel Prize! But so far we have no evidence that any of the fundamental laws of the universe have ever changed.

    23. Rashi was never in EY but he got the right pshat in birashies (35-16) kivras haretz (see Ramban) .
      rashi never weighed a litra but his number was proven recently right over the other reshoniem.

    24. But how is this going against tradition? There were always Poskim, even in recent times, who held that a kezayis is the size of regular olive. E.g. R. Chaim of Volozhin and Avnei Nezer.

    25. Kesayis = the size of an olive in the times of the Beis HaMikdash, when Eretz Yisroel was totally different, as was agricultural growth, as should be known to any kindergarten student who’s learned Chumash. People need to be exceptionally weary of new style rabbis who are kofrim, at least lemaaseh, like David Bar Hayim, with their false and dangerous sophistry.

      David Bar Hayim, your new definitions may be well received by the Jewish Press crowd, who’ve strayed from Judaism and invented a new path, but their machti es harabim and vosizneias should be ashamed of itself for giving it a forum.

      • You are incorrect; we have olive pits from the time of the Beit HaMikdash that are identical to the size of today’s olive pits. And as others have pointed out, there are actual olive TREES in Eretz Yisrael that were producing olives in the time of the Beit HaMikdash and those olives are the same size as those of younger olive trees.


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