Shiur #16: Reviewing One’s Learning

  • Rav Tzvi Sinensky
While last week’s shiur considered the proper method for Talmud study, particularly the question of bekiut versus iyun, in this shiur we turn to the question of reviewing one’s learning (chazara). We will first outline a number of texts in which Chazal warn against the dangers of forgetting Torah, and recommend practical suggestions to better retain one’s learning. We will then seek to better understand the underlying significance of the importance of chazara (review).
Rabbi Dostai the son of Rabbi Yannai would say in the name of Rabbi Meir: Whoever forgets even a single word of one’s learning is liable to the death penalty in the eyes of the verse, as it is stated, "Just be careful, and verily guard your life, lest you forget the things that your eyes have seen" (Devarim 4:9). One might think that this applies also to one whose studies prove overwhelming, but the verse goes on to tell us "and lest they be removed from your heart, throughout the days of your life." Hence, one is not liable to the death penalty unless one deliberately removes them from one’s heart. (Avot 3:8)
Resh Lakish further said: One who makes oneself forget a word of one’s study transgresses a negative precept, for it is written, “Just be careful, and verily guard your life, lest you forget the things that your eyes have seen." (Menachot 99b)
Chazal regularly caution against the dangers of forgetting one’s learning. Even if we do not take this phraseology literally, these sources effectively impress upon the reader the gravity of forgetting Torah. That the verse cited concerns the importance of recalling the Sinaitic Revelation only heightens the severity of the admonition. Indeed, the Vilna Gaon, according to legend, did not evaluate his students’ accomplishments based on their initial study but upon their commitment to engage in chazara.[1]
Similarly, Ta’anit 7a-b discusses the preservation of Torah knowledge.
Rabbi Oshaya said: Why are the words of the Torah likened unto these three liquids, water, wine and milk — as it is written, “Ho, everyone that thirsts come for water;” and it is written, “Come, buy and eat; yea, come buy wine and milk without money, and without price?” This is to teach you, just as these three liquids can only be preserved in the most inferior of vessels, so too the words of the Torah endure only with one who is humble…
Another explanation: Just as these three liquids can become unfit for consumption only through inattention, so too the words of the Torah are forgotten only through inattention.
Thus, Torah cannot last in one who focuses on image or is otherwise distracted. Even great scholars may stumble in this matter when they leave places of Torah; Berakhot 18b tells how Rabbi Chiya’s sons found that “their learning became too heavy for them” while they tended to the land they had inherited; while Shabbat 147b recounts how Rabbi Elazar ben Arakh moved to a pleasant clime in the north of Israel but forgot his learning.
Rabbi Elazar ben Arakh visited that place. He was attracted to them, and [in consequence] his learning vanished. When he returned, he arose to read the Torah scroll. He wished to read (Shemot 12:2): “Ha-chodesh ha-zeh lakhem” (“This month shall be unto you”), but instead he read “Ha-charesh haya libbam” (“Their hearts were silent”).
Nevertheless, the scholars prayed for him, and his learning returned.
And it is thus that we learnt, Rabbi Nehorai said: “Be exiled to a place of Torah, and say not that it will follow you, for it is your companions who will establish it in your possession; and do not rely on your own understanding.”
Emotional turmoil can also be dangerous. “One who loses his temper,” warns Rabbi Yirmeya of Difti (Nedarim 22b), “forgets his learning and increases in foolishness.” On Temura 16a, we find criticism of the premier student, Yehoshua, for his arrogance:
Rav Yehuda reported in the name of Rav: When Moshe departed [this world] for the Garden of Eden, he said to Yehoshua: “Ask me concerning all the doubts you have.”
He replied to him: “My Master, have I ever left you for one hour and gone elsewhere? Did you not write concerning me in the Torah: ‘But his servant Yehoshua the son of Nun departed not out of the tent’?”
Immediately the strength [of Moshe] weakened, and [Yehoshua] forgot 300 laws and there arose [in his mind] 700 doubts [concerning laws].
This shows that attitude is also a factor in retaining one’s learning. Indeed, Rabbi Acha bar Chanina (Eruvin 64a) states “Whosoever says: ‘This ruling is a fine one’ or ‘That ruling is not a fine one’ loses the substance of the Torah.” Rashi explains that such comments dishonor the Torah and cause one to forget it.
Earlier in Eruvin (53a-54b), the Gemara offers numerous tips for retaining one’s learning. Beruria sharply critiques a student who whispers his studies rather than raising his voice, citing a verse indicating that one ought to learn with all 248 limbs. Judeans retained their study because they were precise in their use of language, used mnemonics, studied from a single teacher and “revealed the text.” (Rashi has two explanations of the last phrase: either through teaching others or by studying in depth.) In addition, the Gemara recommends that one split up one’s study into smaller segments, rather than attempting to digest too much at once.
In Pesachim 3b, Rav Huna cites Rav (some attribute it originally to Rabbi Meir) to recommend that one always teach in a shorthand manner; Rashi (s.v. Ve-khol) explains that this ensures that the students better retain their learning.[2]
Why is forgetting one’s Torah so disastrous? The simplest explanation is that this undermines one’s learning. If the purpose of learning is results-oriented, losing one’s knowledge is a failure, in some measure, to fulfill the initial obligation of talmud Torah. Secondarily, there may be an independent problem of forgetting one’s learning. Perhaps one who forgets Torah evinces implicit disrespect toward the Torah; alternatively, assuming that Torah study helps one develop a Torah personality, an aspect of one’s spiritual refinement has been lost.
Different sugyot seem to offer different answers to this key conceptual question. Kiddushin 30a, as noted in previous shiurim in this series, requires that one achieve a level of mastery such that one is able to respond immediately to Torah queries. This may be taken to imply that one who forgets has essentially undermined the objective of attaining Torah knowledge. Indeed, Rav Shneur Zalman of Lyady, who uses this source to prove that attaining Torah knowledge is an essential component of talmud Torah, makes precisely this point. Similarly, Sanhedrin 99b compares one who forgets his learning to a person who sows a field but fails to glean or who loses a child. These metaphors, while bearing slightly different implications, both indicate that retaining one’s learning is essential to the initial act of study, as in Kiddushin 30a. Since the goal of learning is to apply it in practice, one who forgets it has accomplished nothing material.
Chagiga 9b, on the other hand, opens the door to another interpretation. The Gemara teaches:
Bar Hei-Hei said to Hillel: What is that which is written: “Then you shall again discern between the righteous and the wicked, between one who serves God and one who does not serve Him” (Malakhi 3:18)? “The righteous” is equivalent to “one who serves God,” and “the wicked” is equivalent to “one who does not serve Him”!
[Hillel] said to him: The “one who serves God” and the “one who does not serve Him” are both perfectly righteous people, but one who reviews one’s study 100 times is not comparable to one who reviews one’s study 101 times.
Hillel’s key insight — that there is a fundamental difference between one who studies 100 times and one who studies 101, and that only the latter is considered a servant of God — cries out for explanation. While different interpretations have been offered, Hillel’s basic point is that the extent of one’s chazara is essential not just to one’s study but to one’s standing as a servant of God. This sugya, then, lends support to the latter approach we proposed, namely that one who forgets Torah has somehow disparaged the seriousness of one’s study.
Now let us return to Avot 3:8, mentioned at the shiur’s outset. As noted, Rabbi Meir emphasizes that one who intentionally forgets his learning is liable to death. What is more, he cites a verse concerning forgetting the Revelation at Sinai in support of the ruling. Why should such an individual be liable to death? The association with Sinai implies that the prohibition involves something more than merely undermining one’s initial study. Rather, it would appear that one who forgets shows disdain for the Torah and has implicitly spurned the Revelation at Sinai. While, as noted earlier, Rabbi Meir speaks specifically of one who intentionally forgets one’s learning, his statement may well serve as a paradigm for the importance of review more generally.
This latter interpretation is particularly consistent with the view of Ramban, who maintains (Sefer Ha-mitzvot, Negative 2) that Rambam errs in not counting a biblical prohibition against forgetting the events of Sinai, based on the verse cited by Rabbi Meir and Reish Lakish. They indicate that forgetting Torah study is comparable to forgetting Sinai, a terrible sign of disrespect. What is more, based on these statements, Semag (Negative 13) and Semak (Negative 15) enumerate a biblical prohibition against forgetting one’s Torah. This lends further support to this second interpretation, according to which one who forgets one’s learning effectively forgets the events of Sinai.
Interestingly, Rav Chayim Volozhin (Keter Rosh 87) cites the Vilna Gaon’s ruling that the Mishna’s prohibition against forgetting Torah is no longer applicable nowadays. What is the reasoning for this position? Rav Yitzchak Zev Soloveitchik explains that forgetting one’s Torah study undermined the telos of the Oral Torah, which must be committed to memory. Nowadays, however, as the Oral Torah has been set to writing, this halakha is no longer in force. Rav Shneur Zalman of Lyady (Hilkhot Talmud Torah 2:4) vigorously disagrees with this innovative position, insisting that the prohibition against forgetting Torah remain fully intact. (This parallels the debate we saw last week between Rav Shelomo Kluger and Pri Megadim.)  
This dispute may depend on the question we raised above. Rav Shneur Zalman, who emphasizes achieving mastery of Torah, views forgetting Torah as undermining one’s very purpose in engaging in study. The Vilna Gaon, however, sees the prohibition against forgetting Torah as growing not out of the initial impetus for talmud Torah, but out of a particular detail related to the nature of the Oral Torah. In other words, if remembering Torah is essential to the act of talmud Torah, the prohibition against forgetting must, by definition, remain in force nowadays. If, however, we see remembering Torah as external to the basic obligation of talmud Torah, there might be room to contend that the prohibition is no longer in force.

[1] Peninei Halakha 1:10, pg. 21.
[2] See, however, Rambam, Hilkhot De’ot 2:4, who seems to take a different approach to the sugya