Shiur #22: Lo Ba-Shamayim Hi

  • Rav Assaf Bednarsh
Adapted by Leora Bednarsh
The well-known principle of lo ba-shamayim hi, which teaches that the halakha is not determined in Heaven, is found in the following passage:
We learned in a mishna there (Keilim 5:10): If one cut [an earthenware oven widthwise] into segments, and placed sand between each and every segment, R. Eliezer deems it ritually pure. [Because of the sand, its legal status is not that of a complete vessel, and therefore it is not susceptible to ritual impurity.] And the Rabbis deem it ritually impure, [as it is functionally a complete oven,] and this is known as the oven of akhnai. [The gemara asks:] What is the relevance of akhnai, a snake, in this context? R. Yehuda said that Shmuel said: It is characterized in that manner due to the fact that the Rabbis surrounded it with their statements like this snake [which often forms a coil when at rest] and deemed it impure. The Sages taught: On that day [when they discussed this matter], R. Eliezer answered all possible answers in the world to support his opinion, but the Rabbis did not accept his explanations from him. [After failing to convince the Rabbis logically,] he said to them: If the halakha is in accordance with my opinion, this carob tree will prove it. The carob tree was uprooted from its place one hundred cubits, and some say four hundred cubits. The Rabbis said to him: One does not cite halakhic proof from the carob tree. He then said to them: If the halakha is in accordance with my opinion, the stream will prove it. The water in the stream turned backward [and began flowing in the opposite direction]. They said to him: One does not cite halakhic proof from a stream. He then said to them: If the halakha is in accordance with my opinion, the walls of the study hall will prove it. The walls of the study hall leaned inward and began to fall. R. Yehoshua scolded the walls and said to them: If Torah scholars are contending with each other in matters of halakha, what is the nature of your involvement in this dispute? [The gemara relates:] They [the walls] did not fall because of the deference due R. Yehoshua, but they did not straighten because of the deference due R. Eliezer, and they still remain leaning. He [R. Eliezer] then said to them: If the halakha is in accordance with my opinion, Heaven will prove it. A Divine Voice emerged from Heaven and said: Why are you differing with R. Eliezer, as the halakha is in accordance with his opinion in every place that he expresses an opinion? R. Yehoshua stood on his feet and said: [It is written:] “It is not in heaven” (Devarim 30:12). [The gemara asks:] What is the relevance of the phrase “It is not in heaven” in this context? R. Yirmeya says: Since the Torah was already given at Mount Sinai, we do not regard a Divine Voice, as You already wrote at Mount Sinai in the Torah: “After a majority to incline” (Shemot 23:2). [Since the majority of Rabbis disagreed with R. Eliezer’s opinion, the halakha is not ruled in accordance with his opinion.]
R. Natan encountered Eliyahu [Ha-Navi] and said to him: What did the Holy One, Blessed be He, do at that time [when R. Yehoshua issued his declaration]? He said to him: He smiled and said: My children have triumphed over Me; My children have triumphed over Me. (Bava Metzia 59a-b)
Scope of the Principle: Two Tosafist Views
First, we will analyze the scope of this principle.
The gemara in Yevamot 14a tells us that a bat kol, a heavenly voice, rang out and announced that the halakha follows Beit Hillel whenever they argue with Beit Shammai. The gemara there assumes that R. Yehoshua, who ignored the bat kol in the case of the “Oven of Akhnai,” would hold that the halakha does not follow Beit Hillel, as the halakha is not determined in Heaven. Tosafot wonder: If, in fact, we follow the conclusion in Bava Metzia, in which God Himself endorses the principle of lo ba-shamayim hi, why does the halakha follow Beit Hillel?[1]
Tosafot suggest two approaches to resolving this difficulty. According to one answer in Tosafot, the general rule is that we do, in fact, decide the halakha based on a heavenly voice or other supernatural proof. Only in the case of the “Oven of Akhnai, where R. Eliezer demanded explicitly that a heavenly voice attest to the correctness of his opinion, do we suspect that the heavenly voice might have fibbed in order to preserve the honor of R. Eliezer. Tosafot assumes that God is so concerned for the honor of Torah scholars that He would even send out a false message to protect R. Eliezer's honor – even though R. Eliezer foolishly backed himself into a corner by demanding heavenly evidence – and that God would rely on the assembled Sages to know better than to heed this white lie (and, indeed, they did know better).
According to the second opinion in Tosafot, we accept the conclusion of the story of the “Oven of Akhnai” and assume that supernatural evidence cannot override the normal workings of the halakhic process. The heavenly voice that favored R. Eliezer has no authority to override the principle of majority rule that was referenced by R. Yehoshua. However, we do grant authority to the heavenly voice that decided in favor of Beit Hillel, because, as mentioned in the gemara there, there was no clear majority on the side of Beit Shammai. Beit Hillel was numerically larger than Beit Shammai, but it was universally acknowledged that the Sages of Beit Shammai were sharper that those of Beit Hillel. Apparently, Beit Shammai and Beit Hillel disagreed regarding the question of whether the halakha should follow the school with the larger population or the one with more intellectual prowess. This created a logical conundrum, for according to Beit Hillel's opinion, Beit Hillel was in the majority and therefore should be followed, but according to Beit Shammai, Beit Shammai constituted the majority and their opinion must be followed. In such a case, where the standard halakhic process has no way of resolving the dispute, there is room for a heavenly voice to intervene and tell us what to decide.
According to this opinion, supernatural evidence does have authority within the halakhic process, but only when it does not contradict the accepted rules of halakhic decision making.
Scope of the Principle: Rambam
The Rambam seems to have a third opinion about the scope of this principle. He writes that if anyone were to bring supernatural proof to buttress a claim that we should add, subtract, or modify a mitzva of the Torah, he is to be considered a false prophet and is liable to receive the death penalty. Likewise, adds the Rambam, even if this person were merely to claim that the halakha should follow a particular side of a dispute, he is considered a false prophet, because he contradicts the principle of lo ba-shamayim hi.[2] The Rambam thus assumes that the principle of lo ba-shamayim hi is universal and allows no exceptions. Even in the case of an unresolved halakhic dispute, where there may be no clear halakhic precedent that dictates whom the halakha should follow, it is anathema to bring supernatural evidence and involve the Heavens in an earthly halakhic dispute.
According to the Rambam, the heavenly voice that favored Beit Hillel is granted no authority whatsoever. We must therefore conclude  that the halakha follows Beit Hillel not because of any heavenly voice, but rather because the majority of Sages in the later generations agreed with the logic of Beit Hillel, in accordance with the normal halakhic process.
Scope of the Principle: Summary
We have seen three opinions about the scope of the disqualification of supernatural evidence within the halakhic process. One opinion in Tosafot holds that supernatural evidence is always admissible, except in cases in which there is strong reason to suspect an ulterior motive, such as to save a Torah scholar from embarrassment. A second opinion in Tosafot believes that supernatural evidence is admissible only when the halakhic process cannot arrive at a firm conclusion, but not when the accepted halakhic principles suffice. A third opinion is found in the Rambam, who holds that supernatural evidence is never admissible in the halakhic process.
It is interesting to note that one of the Tosafists, R. Yaakov of Marvege,[3] wrote an entire work, titled Shu”t Min Ha-Shamayim, Responsa From Heaven, which reports halakhic decisions that he received from the heavenly academy in his dreams. Such a work could never have been written by the Rambam, as he does not give credence to the halakhic opinion of the heavenly academy. However, according to the Tosafists, it is logical that R. Yaakov of Marvege ruled based on what he learned from the heavenly academy, as these rulings were not given to protect anyone's honor and presumably only dealt with undecided halakhic issues that could not be successfully resolved through the earthly halakhic process.[4]
Justification of the Principle
A second question that emerges from the story of the “Oven of Akhnai” relates not to the scope, but rather to the justification of the principle of lo ba-shamayim hi. If God revealed His halakhic opinion by means of a heavenly voice or other objective evidence, how can we rule otherwise? To paraphrase the language quoted in the name of God Himself, how is it legitimate for us to “triumph over God” if the goal of halakhic observance is to fulfill God's will? Shouldn't the overriding principle of the process of determining halakha be the wish to fulfill the will of God?
Justification: Two answers of R. Nissim Gaon
This question is raised by R. Nissim Gaon.[5] His first answer is that, in fact, we did not rule in contradiction to the heavenly voice. He points out that the heavenly voice announced, seemingly verbosely, that the halakha follows Rabbi Eliezer in all places. While we may have understood (and so indeed understood R. Eliezer himself) that the heavenly voice intended to relate that the halakha followed R. Eliezer in this particular dispute, and it merely added that the halakha follows him in all places in order to further bolster his credibility, R. Nissim Gaon understands that the heavenly voice meant this formulation as a hint that the halakha follows R. Eliezer in all other places, but not in this dispute. The majority of the Sages, then, were not contradicting the heavenly revelation, but rather following its true intent.
R. Nissim Gaon also suggests a second approach in which he admits that the Sages disregarded the heavenly voice, but claims that they nonetheless did not contradict the opinion of God Himself. He points out that the Torah itself states unequivocally that God may grant a false prophet supernatural powers in order to test the Jewish People (Devarim 13:2-6). Even an authentic heavenly miracle, if brought in support of a position that contradicts the Torah, is merely a test to see if our loyalty to Halakha will remain steadfast even in such extreme circumstances. Likewise, the heavenly voice that supported R. Eliezer was in fact sent by God, but did not represent His true halakhic opinion. The Sages were being tested to see whether they would follow the misleading heavenly voice or the true will of God as revealed through the halakhic process, and they passed the test.
Both interpretations given by R. Nissim Gaon dull the philosophical edge of this principle. We ignore heavenly proclamations not because we prefer human reasoning over divine logic, but because the heavenly voice – though it originates in Heaven – does not necessarily represent an authentic heavenly conclusion. The Sages did not literally triumph over God by ruling against R. Eliezer, but only overruled the deceptively formulated or disingenuous heavenly voice in order to successfully discern the true will of God.
The impression given by the story of the “Oven of Akhnai,” however, does not support the reading of R. Nissim Gaon. The closing scene, in which God Himself says that the Sages triumphed over Him, implies that God indeed ruled in accordance with R. Eliezer, but He was nonetheless pleased that the Sages followed human logic and the majority vote in disregard of Divine truth.  Apparently, following the earthly halakhic process is more important than fulfilling the halakha in accordance with God's original intention. God Himself was pleased that we followed His will regarding the proper procedure for resolving halakhic disputes, even though it negated His will regarding the substance of the particular halakhic question at hand.
Justification: Two Answers of the Ran
The Ran, in his philosophical work Derashot Ha-Ran,[6] understands the principle of lo ba-shamayim hi in the context of a broader principle derived by Chazal regarding the commandment, “Do not stray from the matter that they tell you, neither right nor left” (Devarim 17:11). Chazal derive from the verse that one is obligated to follow the rulings of the Sanhedrin, the highest court, even if they were to tell you that right is left and that left is right.[7] The Ran understands that one should follow the authorized halakhic decisors not only if it merely seems to him that they are mistaken, but even if they are actually completely wrong. Even if their ruling is as erroneous as the statement that right is left and left is right, one is nonetheless commanded to follow them. Therefore, the Sages followed the majority opinion over the opinion of R. Eliezer, even in the face of valid proof that he was correct, because we are commanded to follow the standard halakhic procedure based on human logic, whether it represents ultimate truth or utter falsehood.
The Ran suggests a number of reasons why the Torah would command us to follow human reasoning over supernatural revelation in deciding Halakha. First, it is impractical to make the Halakha dependent on the power of prophecy or access to the supernatural, because not every generation merits prophecy or supernatural providence, and we would then be unable able to reach firm halakhic conclusions. Intellectual understanding of Torah, however, can be found in all generations. More importantly, logical reasoning can be analyzed and rebutted and subject to a degree of scrutiny that would ferret out any vacuous arguments or hidden errors. Supernatural proofs, however, can easily be falsified. It is not difficult for a charlatan to convince the gullible masses, and even great Sages, that he is a prophet or miracle worker, producing what seem to be signs and wonders to buttress his claim. We are much more likely to achieve accurate halakhic rulings, not to mention religious stability, if halakhic authority is restricted to logical reasoning, to the exclusion of supernatural proofs. Even in the case of the “Oven of Akhnai,” in which R. Eliezer's proofs certainly seemed legitimate, it is preferable to rule inaccurately with regard to one particular oven, while preserving the stability of the halakhic process for eternity.
The Ran is still bothered, however, by the audaciousness of knowingly ruling and practicing halakha in violation of the actual will of God. He points out that according to mainstream Jewish thought, every positive commandment in the Torah was commanded by God because its fulfillment generates some substantive spiritual benefit, and every transgression forbidden by the Torah was forbidden because its performance causes substantive spiritual damage to our souls. If so, asks the Ran, how can we justify following the accepted halakhic process when it reaches a conclusion that is known to be incorrect? Just as a medical consensus that poison is harmless cannot save one who ingests it from the damaging effects of the poison, so too, no rabbinic consensus can save our souls from the objective damage caused by following an incorrect halakhic ruling.
The Ran's first solution to this problem is based on a philosophical premise found already in the Rambam's Moreh Nevukhim:[8] The Halakha is not meant to benefit everyone who follows it in all circumstances, but rather to benefit the world as a whole. The Halakha brings spiritual benefit to most people under most circumstances, but not in all circumstances. Therefore, the halakha of lo ba-shamayim hi dictates that in the exceedingly rare occasion of a mistaken ruling on the part of the highest halakhic authorities, individuals bound by those rulings should indeed incur spiritual damage by following those rulings, in order to preserve the system and bring spiritual benefit to themselves and to the rest of the Jewish People in the 99.9% of cases in which the halakhic authorities decide the halakha correctly. According to this theory, it is not theologically problematic if the spiritual medicine of halakhic observance causes detrimental side effects in exceedingly rare circumstances.
The Ran's second approach to dealing with this problem assumes that the Halakha is universally beneficial, and that even in the rare circumstances covered by the principle lo ba-shamayim hi, one would never suffer spiritual damage by following the Halakha. One who follows the majority opinion of the Sages, even if it contradicts the actual halakhic truth as known in Heaven, will not be spiritually harmed at all by his defective observance, because the salutary effects of accepting rabbinic authority will negate any possible spiritual harm that could ensue from the specific defective action he performs. The Ran points out that just as in the realm of physical health, ingesting unhealthy substances can be harmless under certain conditions, even an act that would otherwise be spiritually harmful may in fact be harmless in the context of upholding a principle that is greatly beloved by God and exceedingly beneficial for spiritual development.
Both explanations of the Ran agree fundamentally that the principle of lo ba-shamayim hi obligates us to give preference to global, procedural principles over specific substantive accuracy, and that it is worthwhile to act wrongly in a particular matter in order to preserve and protect the system of Halakha. Any spiritual harm that would ensue from such wrong action is either very rare and a worthwhile sacrifice, or will be neutralized and rendered harmless from the outset.
Justification: Ketzot Ha-Choshen
The Ketzot Ha-Choshen advocates a bolder perspective on the principle of lo ba-shamayim hi.[9] He begins by presenting a conundrum: The Zohar praises the creative accomplishments of those who innovate "chiddushei Torah," novel Torah insights. However, ask the Ketzot Ha-Choshen, how can we add anything new to the Torah? Anything that is true is already found in the Torah, and that which is false is not worthy of being propounded!
He answers by quoting the Ran and adding that by giving the Torah to human beings, who are fundamentally incapable of fully understanding Divine wisdom, God redefined the nature of ultimate truth and elected to prefer the truth that emerges from the best efforts of human logic, however imperfect and inaccurate it may be, to the ultimate truth found only in Heaven. In fact, by creating man and making our service of God the goal of creation, God expressed His desire for human "truth" over the ultimate truth favored by the angels who argued against the creation of man.[10] God wants us to be His partners in developing the truth of the Torah, and that goal is so valuable that it overrides the value of ultimate truth.
The Ketzot Ha-Choshen interprets the language of our daily birkot ha-Torah, "an everlasting life He implanted in our midst," as an answer to the Ran's comparison of following an incorrect ruling to ingesting poison. When one ingests poison, it remains poison. But God implanted everlasting life in our midst by giving us the Torah; He implanted within us the ability to create everlasting life via novel Torah interpretations. When the Sages, following proper halakhic process, declare something permitted, then even if previously it was spiritually poisonous, it becomes benign or even beneficial. The very human process of halakhic development has the power to make certain actions spiritually beneficial or detrimental, and if that requires a rewiring of the spiritual workings of the heavenly and earthly realms, then God has committed Himself to adapting His reality to the decisions of the Torah Sages.
According to this bold theory, the Sages in the story of the “Oven of Akhnai” indeed triumphed over God, and this is precisely what God intended when He gave the Torah to human beings instead of angels. The mystery of why God desires the partnership of human beings in developing His Torah transcends our intellectual grasp, but the Ketzot Ha-Choshen is convinced that it is this mystery that underlies the meta-halakhic principle of lo ba-shamayim hi. 
We have seen three basic approaches to understanding the philosophical basis of lo ba-shamayim hi.
According to R. Nissim Gaon, our goal is to discern and follow the will of God in accordance with heavenly truth. However, in order to do so, we must sometimes discount ostensible supernatural proofs, and the principle of lo ba-shamayim hi teaches us that not everything that appears to reflect divine revelation indeed does so.
According to the Ran, we are obligated on rare occasions to discount the actual heavenly truth and act deficiently in specific situations, out of concern for preservation of the halakhic system as a whole. It is worthwhile sacrifice, or perhaps not even a sacrifice, to err in a particular matter in order to preserve halakhic integrity and religious unity.
Finally, according to the Ketzot Ha-Choshen, it is not only necessary but desirable to diverge from the ultimate heavenly truth and follow the conclusions of human Torah logic. If God wanted heavenly truth, he would have listened to the angelic lobbyists who urged Him to keep the Torah up in Heaven. God gave us the Torah so that we would be not only His subjects but His partners in bringing spiritual truth into the physical realm, and it is precisely on those occasions in which human truth overrides heavenly truth that we realize our destiny and become God's partners in revealing the Torah.

[1] Tosafot, Yevamot 14a, Bava Metzia 59b, Chullin 44b. See also Tosafot, Berakhot 52a and Pesachim 114a.
[2] Mishneh Torah, Hilkhot Yesodei Ha-Torah 9:1-4.
[3] Marvege, France, 12-13th century.
[4] R. Ovadia Yosef, however, rules that one should definitely give no credence to the Shu”t Min Ha-Shamayim, because even Tosafot only gave credence to a heavenly voice or other objective supernatural event that is observed by a multitude of people. Dreams, in contrast, have no credence whatsoever, as they represent merely the thoughts of the dreamer himself and are not necessarily sent from Heaven (Responsa Yabia Omer, vol. 1, Orach Chaim 41).
[5] R. Nissim ben Yaakov (Tunisia, 990 – c.1060), commentary to Berakhot 19b.
[6] R. Nissim ben Reuven of Gerona (Spain, c. 1320-1376), Derashot Ha-Ran, ch. 11.
[7] Sifrei, ad loc., quoted by Rashi, ad loc. See also Yerushalmi, Horayot 1:1, and the comments of the Divrei David and Ha-Ketav Ve-Ha-Kabbala to this verse.
[8] Moreh Nevukhim 3:24.
[9] R. Aryeh Leib Heller (Galicia, 1745-1812), Ketzot Ha-Choshen, introduction.
[10] Bereishit Rabbah, Parashat Bereishit 8:5.