Uprooted Rationales (Column 619)

With God’s help

Disclaimer: This post was translated from Hebrew using AI (ChatGPT 5 Thinking), so there may be inaccuracies or nuances lost. If something seems unclear, please refer to the Hebrew original or contact us for clarification.

In the previous column I discussed what I called “uprooted halakhot,” namely verses that seem to contain legal commandments but—due to the absence of treatment in Hazal—do not attain binding halakhic status. A few days ago a discussion arose between me and my daughter Rivka about verses in the Torah that state a rationale (a ta’am), which raised an adjacent question I’ll now call “uprooted rationales”: what do we do with verses that state the rationale for a mitzvah? Do they have halakhic significance? In this column I’ll touch on that question.

The Bach on special intentions in mitzvot whose rationale the Torah explicates

At the beginning of the laws of Sukkah, the Tur devotes an entire section to the historical–intellectual background of Sukkot (siman 625) and writes as follows:

“‘You shall dwell in booths for seven days … so that your generations shall know that I made the children of Israel dwell in booths when I brought them out …’—Scripture linked the commandment of Sukkah to the Exodus from Egypt, and so too with many mitzvot, because it is something we saw with our own eyes and heard with our own ears, and no person can deny it. It testifies to the truth of the existence of the Blessed Creator, that He created everything according to His will and that He alone has the power, dominion, and ability in the upper and lower worlds to do with them as He wishes, and there is none to say to Him, ‘What are You doing?’—as He did with us when He brought us out of the land of Egypt with signs and wonders. And the booths in which Scripture says He made us dwell were the Clouds of His Glory, with which He encompassed them so that heat and sun would not strike them; and as a model of this He commanded us to make sukkot, so that we remember His wonders and awe. And even though we left Egypt in the month of Nisan, He did not command us to make a sukkah at that time because it is summer, and everyone naturally makes a shade-hut for relief, and our making would not be recognizable as being for the command of the Blessed Creator. Therefore He commanded us to make [the sukkah] in the seventh month, the rainy season, when everyone leaves his sukkah and sits in his house, while we leave our homes to sit in the sukkah; thereby it will be evident to all that the King’s command is upon us. And this sukkah must be in a place fit for it, from suitable materials; its walls must be proper in their measures and number; its roofing proper; it must not be higher than its measure nor lower than its measure, nor smaller than its measure.”

These words are repeated briefly in the Shulchan Aruch in the same section.

The Bach there wonders why the Tur devoted so much space to this, contrary to his usual practice, and writes:

“‘You shall dwell in booths …’—he linked [the mitzvah] etc. One may ask on our master’s words, for this is not his way in this work to explain the intention of verses in the Torah, since he came only to rule law or teach practice. Yet here he lengthened to expound the verse of ‘You shall dwell in booths.’ It seems to me to say that he holds that since it is written ‘so that your generations shall know,’ one has not fulfilled the mitzvah properly unless he knows the intention of the mitzvah of sukkah according to its simple meaning. Therefore he explained, according to the plain sense, that the principal intention in dwelling in the sukkah is to remember the Exodus from Egypt. And this is the very reason for our master’s words where he wrote in the laws of Tzitzit in siman 8 (p. 25): ‘And he should intend, when enwrapping himself, that the Omnipresent commanded us …’ and likewise in the laws of Tefillin in siman 25 (p. 71) he wrote: ‘And he should intend, when putting them on, that the Omnipresent commanded us to put them on … so that …’—which he did not do in other laws, for he did not write that one should intend any intention when performing a mitzvah, because one who fulfills a mitzvah according to its law discharges [his obligation] even if he had no intention; but with Tzitzit it is written (Num. 15:40) ‘so that you shall remember,’ and regarding Tefillin it is written (Ex. 13:9) ‘so that the Torah of the Lord shall be in your mouth,’ whose plain meaning is that the Tefillin are a sign and remembrance so that the Torah of the Lord will be fluent in our mouths, for with a mighty hand He took you out. It appears that one has not fulfilled the mitzvah properly unless he intends that intention. Therefore he wrote in those laws: ‘and he should intend …’ And likewise regarding Sukkah, since it is written ‘so that your generations shall know,’ it implies that one must intend, at the time of dwelling in the sukkah, the rationale intended by the mitzvah.”

The Bach argues that wherever the Torah states the rationale of a mitzvah, there is a special requirement to know and intend that rationale at the time of performance. In his view, this intention is required in order to discharge the obligation, beyond the ordinary intent required in all mitzvot to fulfill a command (i.e., lishmah).[1] The Mishnah Berurah there (sk. 1) quotes the Pri Megadim that this does not invalidate ex post facto, but the intention is required to perform the mitzvah in its optimal, “proper” manner (as also implied by the Tur’s language the Bach cites regarding Tzitzit and Tefillin). Several later authorities also discuss whether this intention invalidates (or at least is required) only on the first night, when there is an obligation to eat in the sukkah, or whether it applies throughout the festival (where the mitzvah is conditional—if one eats or sleeps, he must do so in the sukkah).

Before I proceed, I must say that it seems very unlikely to me that this was the intention of the Tur and the Shulchan Aruch. Otherwise, they ought to have explicitly stated the halakhah that one is obligated to intend. For some reason they tell us the whole story at length but do not bother to state the halakhic takeaway, which is the main point. Note that in the laws of Tzitzit and Tefillin the Tur does explicitly mention the intention (though not as a strict obligation, as above), but in the laws of Sukkah he does not. Moreover, the Beit Yosef himself engages these words of the Tur and explains them in detail without mentioning a special duty to intend even once. So at least for him (in the Shulchan Aruch) it is quite clear this is not the explanation. Still, this is the view of the Bach and other later authorities.

At first glance, the claim itself has much logic. Usually the Torah states a command—positive or negative—without stating its rationale. Thus the question arises: why did the Torah choose to state the rationale here? It seems natural to infer that it wishes to instruct us to direct special intentions in these mitzvot. It would follow that in Sukkah one must intend a special intention, and likewise in Tzitzit (“so that you shall remember”) and Tefillin (“so that the Torah of the Lord shall be in your mouth”), and others.

We find something similar in Rosh HaShanah 28a–b in the sugya of whether mitzvot require intent:

“Rava said: This teaches that one who sounded [the shofar] for music has fulfilled [his obligation]. Isn’t that obvious? It is the same [as eating matzah without intent]. You might have said: There [with matzah] the Merciful One said ‘You shall eat matzah’ and he ate; but here it is written ‘a memorial of teruah,’ and this one is merely engaged [without intent]. [Therefore] it teaches us [that even here he discharges].”

The discussion concerns one who blew the shofar on Rosh HaShanah for another purpose (not for the mitzvah, i.e., without intent). Rava says he fulfilled the obligation. The Gemara explains that Rava needed to say this, even though his general view is that mitzvot do not require intent, because regarding shofar one might have thought that even if ordinary mitzvot do not require intent, here one does, since it says “a memorial of teruah.” Even so, this is only a rejected possibility, and the conclusion is that there is no special duty to intend. This further strengthens my doubt whether the Bach is correct regarding mitzvot whose rationale is explicit in Scripture.

The Bach’s interpretive claim

In Minchat Asher – Kelalei HaMitzvot this is generalized: for any mitzvah whose rationale the Torah adds, one must intend that rationale when performing the mitzvah—even according to those who say mitzvot do not require intent. In practice, I suspect almost no one is meticulous about this (perhaps aside from Sukkah due to the Bach), and as we saw, this seems to be implied by the silence of the halakhic decisors and by the Gemara in Rosh HaShanah. Yet the matter requires explanation, for as I explained above, the Bach’s claim is, on the surface, reasonable and compelling.

Let me sharpen the Bach’s claim. The usual intent in mitzvot is external to the content of the mitzvah itself. For example, when I take the Four Species I perform a mitzvah with some content not explicit in the verse, and in addition halakhah requires me to intend when doing it. That requirement is not tied to the specific content of this mitzvah; it is a general rule for mitzvah performance. Therefore the content of the intention is not tied to the Four Species at all but to the fact that I am doing this to discharge my obligation. The intention here is the same as the intention required in any other mitzvah. Hence, if I performed a mitzvah without such intention, the mitzvah as such was performed, but there is an external deficiency in the performance that, according to some opinions, can even invalidate it. By contrast, the intentions of which the Bach speaks are specific and tied to the content of the mitzvah itself. In dwelling in the sukkah, one must intend to remember the Exodus, because that is the content of sukkah. Moreover, the intending is part of the mitzvah’s performance, not a general, external condition. He does not only claim that intending to remember the Exodus is me’akev (essential) to dwelling in the sukkah; rather, that this is the very mitzvah: to dwell in order to remember the Exodus. Therefore, if I did not intend “a remembrance of the Exodus” in my sukkah-dwelling, I have not discharged my obligation—because I simply have not performed the mitzvah.

A similar distinction appears in R. Yitzhak Hutner’s remarks on love-commands in halakhah (see Column 22 and my article here). One such mitzvah is loving the convert. R. Hutner contends that if I loved a certain person who happened to be a convert, I have not fulfilled the mitzvah—despite the fact that I have, indeed, loved a convert. What is lacking? Directing the love toward his being a convert. I must love him because he is a convert; only then have I fulfilled the mitzvah. In other words, his conversion is not a mere external condition determining to whom to apply love; it defines the mitzvah itself: to love him because he is a convert. Put differently, the convert-status is not merely the reason for this love-command but the defining criterion for its fulfillment. The Bach’s claim is that ordinary mitzvot have a rationale, but that rationale is not necessarily a defining criterion of the mitzvah’s fulfillment. In mitzvot where the Torah itself explicitly states the rationale, it is telling us that the rationale here is a criterion built into the fulfillment itself. The intent during performance is part of the mitzvah and not merely an external condition.

This, too, can be understood in a few ways. One option is to argue that the Torah is not actually obligating us to dwell in a sukkah. The mitzvah is to remember the Exodus; dwelling in a sukkah is merely the means that prompts that remembrance. On this extreme understanding, the question obviously arises: why dwell in a sukkah at all? One could, for example, put up a large sign reminding us of the Exodus—far more direct and effective. Similarly, just yesterday I was asked regarding Tzitzit: why does it apply specifically to a four-cornered garment? If the goal is to remember the commandments, it should apply to every garment. In fact, one could ask more: why do we need garments and fringes at all? Let’s just hang a big sign to remind us of the commandments—that’s a much more efficient way to remember. It would seem, then, that it is not correct to treat the rationale as the essence of the mitzvah. The mitzvah is not “remember the Exodus” but “dwell in a sukkah.” Remembering the Exodus may be the rationale for the mitzvah or a mode of its fulfillment—but not its essence.

Moreover, if indeed the rationale were itself the mitzvah, then even in mitzvot where the rationale is not written we would have to treat the rationale as the essence of the mitzvah. Every mitzvah has some rationale, even if not written or known to us. In principle, then, even for mitzvot whose rationale is not written, we would have to try to conjecture the rationale and intend it during performance, since that is the essence of the mitzvah’s fulfillment. Without it, the act does not achieve its aim. On the face of it, this should not differ from mitzvot where the rationale is written (aside from the fact that we cannot know it with certainty—though see our article on the Fifth Principle, that even this is hardly necessary). Thus the formulation that the mitzvah is nothing but the rationale likely does not hold water.

A different option is to argue that these special intentions are not the mitzvah’s content itself. The mitzvah is to attach Tzitzit; the remembrance is the mitzvah’s aim and rationale but not its content. Yet by writing the rationale explicitly, the Torah hints that for some reason, in these cases, we should actually intend it when performing the mitzvah. On this understanding, there is an intention that is indeed external to the mitzvah’s content but is additionally required, beyond the ordinary intent required for all mitzvot. On this view, a sign reminding us of the Exodus (instead of dwelling in a sukkah) or of the commandments (instead of wearing Tzitzit) would not help, since the mitzvah is to dwell in a sukkah and to attach Tzitzit. But in parallel there is an additional, essential condition: to intend. This intention is not the mitzvah’s content, but the Torah hints that here intent is necessary.

One could suggest a third, related but not identical, formulation: the mitzvah is to remember the commandments by means of Tzitzit, or to remember the Exodus by means of dwelling in a sukkah. Here the special intent is not external—it is part of the mitzvah’s content—but it cannot be detached from the mandated act and certainly cannot replace it. The mitzvah is not “remember the commandments” or “remember the Exodus,” but to do so in a very specific way. Still, if the goal is remembrance, why insist on these particular means? It seems there is something in the required acts (attaching Tzitzit, dwelling in a sukkah) beyond mere remembrance. The remembrance is added to the act of the mitzvah but is not the whole of it.

This nearly returns us to the previous formulation. There remains a difference, since under the last formulation we must remember the Exodus via dwelling in a sukkah, but not that “remembering the Exodus” is the goal and “dwelling” merely the means. The goal is to remember the Exodus by dwelling in a sukkah. Evidently, the entire complex produces some other result (a metaphysical “repair,” as it were), and that is the mitzvah’s aim. Alternatively, perhaps that stated rationale is only one of the mitzvah’s aims, and there are others. Still, the Bach claims that to achieve the mitzvah’s aims we must intend explicitly during performance. The Torah conveys to us this aim so that we intend it. Even if there are other aims we do not know them, and so we cannot intend them (though it would be fitting to do so if we could).

All these are possible ways to articulate the Bach’s position. Whatever the precise formulation, if we are to explain the view that disputes the Bach—that even for these mitzvot there is no duty to intend—we must seek an alternative explanation for why the Torah wrote these rationales explicitly, contrary to its way in other mitzvot. If we cannot find such an explanation, we end up with the “uprooted verse” problem discussed last time: a verse that says something and yet has no binding halakhic import.

The Rambam and Ramban’s dispute in the Fifth Principle

The question of the significance of rationales explicitly written in the Torah is the subject of the Rambam’s Fifth Principle (of the Sefer HaMitzvot). There he rules that such rationales are not to be counted among the 613 commandments, and he is clearly talking only about rationales written in the Torah (since only for those could one have thought to count them). His claim is that the rationale is not a command at all, but merely an explanation or rationale for the command. For example, regarding the king the Torah states: “He shall not multiply wives for himself, lest his heart turn away,” and plainly the command is a prohibition on the king’s multiplying wives; the rest of the verse provides the rationale: it is forbidden because this may turn his heart away.

This, of course, raises the question: why is this principle needed? Who would count the rationale as a separate mitzvah? Evidently there is a hava amina (initial thought) to the contrary: perhaps there is no prohibition on multiplying wives; the true prohibition is arriving at “the turning away of the heart,” and multiplying wives is merely a state that may induce it. One might even argue that multiplying wives is but one example, among several, of actions that may lead to a turned heart. All such actions would be forbidden, for the prohibition targets the outcome, not the acts themselves. If so, we would count from this verse only one prohibition—but not its first half (“He shall not multiply wives”) rather its second half (“lest his heart turn away”). This, presumably, is the notion the Rambam’s principle rejects. He rules that we count only the first half, as the second is a rationale, not a mitzvah. From the Rambam it emerges that a rationale written in the Torah is not the command itself, but merely its rationale—thus rejecting the first formulation above, that the rationale is the mitzvah. I already explained why that formulation is implausible.

The Ramban, in his glosses to the Fifth Principle, disputes this and writes:

“And I say regarding this principle what the Sages say (Ketubot 54a): ‘At first glance it appears like him, but upon proper examination it is not so.’ For we have not seen our Rabbis in the Talmud treat the Torah’s prohibitions as redundant, making them rationales for the previous prohibition, unless they come to add or detract—meaning, that we learn a novel law from that rationale—as they dispute (Sanhedrin 21a) regarding ‘He shall not multiply wives for himself, lest his heart turn away.’ This latter prohibition is surely a rationale for the earlier prevention from multiplying wives; nonetheless the Sages of Israel disputed it, as R. Yehuda expounds: ‘What is the reason he shall not multiply? Because it may turn away [his heart]’—teaching that he may multiply wives provided they do not turn his heart away, i.e., they are vetted for righteousness; whereas R. Shimon expounds a separate prohibition, saying: ‘Even [if he will take] one who turns his heart away, he shall not marry her.’ If so, why say ‘he shall not multiply’?—even [if they are] like Abigail.”

The Ramban argues that the Torah does not write rationales for mitzvot unless they add some novel halakhic detail; failing that, they are not rationales at all but additional commands (see below regarding the king’s wives). This seems to contradict the Bach, for whom the added rationale is not meant to teach any new detail but to provide the reason and instruct us to intend it. True—if we adopt the first formulation (that the rationale is the mitzvah). But if we adopt either of the latter two, it could be that the verse is indeed written to teach a halakhic detail: namely, that one must intend a special intention in this mitzvah—just as the Bach says. Even so, this is not apparent from the Ramban, who seeks specific, concrete halakhic novelties in each such mitzvah and does not suffice with the general claim that rationales always come to require intent. One might argue that he focuses on prohibitions, where intentions have no legal role; but that itself is an argument against the Bach: if in prohibitions the rationale comes to teach a legal detail, it is plausible that in positive commands the rationale also comes to teach some legal detail—not a duty of special intention. In any case, the argument that compels the Bach (that without such a move, the rationale-verse is superfluous) falls away.

Ta’ama d’Kra: “He shall not multiply wives … lest his heart turn away”

Let’s begin with the Tannaitic dispute over whether we “expound the verse’s rationale” (darshin ta’ama d’kra). Bava Metzia 115a brings the following dispute:

Mishnah: A widow—whether poor or wealthy—may not be taken a pledge from, as it is stated: ‘You shall not take in pledge a widow’s garment’ (Deut. 24).

Gemara: The Sages taught: A widow—whether poor or wealthy—may not be taken a pledge from; these are the words of R. Yehuda. R. Shimon says: A wealthy [widow]—you may take a pledge; a poor [widow]—you may not, because you are obligated to return it to her [daily], and you will bring a bad name upon her among her neighbors [by entering her home at night].

The Torah forbids taking a pledge from a widow, i.e., taking collateral for a loan. The Mishnah explains this applies to any widow, rich or poor (even though the rationale fits only the poor). The baraita records a dispute: R. Shimon holds the prohibition applies only to a poor widow, not a rich one, because in his view the rationale is that returning the pledge nightly will “look bad” to the neighbors (the lender enters her house at night and is secluded with her). That rationale exists only for a poor widow (only she needs the object returned nightly). R. Yehuda probably does not dispute the rationale, but holds that we do not expound the verse’s rationale—it has no halakhic implications. Thus the Tannaim dispute whether we expound a verse’s rationale; and the halakhah is that we do not (see Rambam, Hilkhot Malveh veLoveh 3:1). Note: they are not arguing whether mitzvot have rationales, nor whether it is important to discuss them, and perhaps not even whether we can discover them and be right; the dispute is only whether halakhic interpretation may employ them.

The Ramban, in his gloss to the Fifth Principle cited above, brings Sanhedrin 21a regarding the king’s wives. In our article on the Fifth Principle in the book Yishlach Sharashav, we analyzed this sugya and its implications for ta’ama d’kra in general; here are the details. The Mishnah there discusses the king’s law:

“He shall not multiply wives for himself—only up to eighteen. R. Yehuda says: He may multiply wives for himself, provided they do not turn his heart away. R. Shimon says: Even [if there is] one who turns his heart away, he shall not marry her. If so, why does it say ‘he shall not multiply wives for himself’?—[to prohibit] even [wives as righteous as] Abigail.”

(The number eighteen is derived later in the sugya.) Here we have a Tannaitic dispute. According to R. Yehuda, he may multiply wives who will not turn his heart away; in his view there is one prohibition: the king may not take more than eighteen wicked wives. According to R. Shimon, there are two prohibitions: he may not take even one wicked wife; and righteous women (like Abigail) he may take up to eighteen—but no more. The first prohibition is “turning the heart”; the second is multiplying wives. Already here you see R. Shimon severing the command from the “rationale” verse (which perhaps is not a rationale at all).

At first glance, this inverts what we saw earlier: suddenly R. Yehuda is expounding the rationale and R. Shimon is not. The Gemara raises this:

“Shall we say that R. Yehuda expounds the rationale and R. Shimon does not? But we have heard the opposite of them, as it was taught [re: the widow’s pledge] … Thus R. Yehuda does not expound the rationale and R. Shimon does.”

It resolves:

“In general, R. Yehuda does not expound the rationale; here it is different, for the rationale is explicit in the verse: What is the reason he shall not multiply wives?—because lest his heart turn away. And R. Shimon would say to you: Since in general we do expound the rationale, let Scripture write ‘He shall not multiply wives’ and be silent; then I would say: What is the reason he shall not multiply?—because ‘lest his heart turn away.’ Why, then, add ‘lest his heart turn away’? [To teach that] even one who turns his heart away he shall not marry. And what do I maintain [with] ‘he shall not multiply’?—even [wives like] Abigail.”

R. Yehuda generally does not expound the rationale; but when the rationale is written explicitly, he does. In his view, the Torah wrote the rationale so that we expound it (this is the Ramban’s view—rationales come to add halakhic details). R. Shimon generally does expound rationales, so the Torah would not need to write it (he would have expounded it anyway). Therefore he understands that the “rationale” is not a rationale at all but an additional prohibition: the first clause forbids multiplying wives—even righteous ones—and the second forbids even one wicked wife. According to him, the verse contains two prohibitions, not a command plus a rationale.

On both views, the written rationale comes to teach something, not merely to “explain.” Hence the Ramban challenges the Rambam’s principle: according to both R. Yehuda and R. Shimon, the “rationale” verse has halakhic import. The Ramban argues that the Rambam’s words do not fit either view.

In his Commentary on the Mishnah (Sanhedrin ad loc.) the Rambam writes a cryptic line:

“The halakhah is neither like R. Shimon nor like R. Yehuda.”

These words are puzzling: how can the Rambam rule unlike both Tannaim in a Mishnah? What view does he adopt? And practically, what is the law regarding multiplying wives?

The answer emerges from the Mishneh Torah (Hilkhot Melakhim 3:2):

“‘He shall not multiply wives for himself’—by tradition they learned that he may take up to eighteen wives; between wives and concubines, all together eighteen. If he added one and had relations, he is liable to lashes; he may divorce her and marry another in her stead.”

The Rambam indeed rules differently than both Tannaim: there is one prohibition against the king’s multiplying wives, with no distinction regarding their righteousness. This is not like R. Yehuda (who permits righteous wives) nor like R. Shimon (who forbids even one wicked wife). The Rambam treats the verse’s second half as a rationale, and does not expound it—neither to be lenient nor stringent. The law is fixed by the legal, textual first half (“He shall not multiply wives for himself”), while the second half is merely an explanatory rationale with no halakhic weight.

On whom does the Rambam rely? In the general dispute between R. Yehuda and R. Shimon about expounding rationales, the halakhah follows R. Yehuda (and the Rambam himself rules so). One might think that here, too, he should have ruled like R. Yehuda. It seems the Rambam found a third, anonymous Tannaitic view and follows it.

Indeed, returning to the Mishnah in Sanhedrin, one can read it differently from the usual (and from the Ramban’s reading):

“‘He shall not multiply wives for himself’—only eighteen.”

“R. Yehuda says: He may multiply wives for himself, provided they do not turn his heart away.”

“R. Shimon says: Even [if there is] one who turns his heart away, he shall not marry her. If so, why does it say ‘he shall not multiply wives for himself’?—even [wives like] Abigail.”

Most commentators (with the Ramban) take the opening line as a “heading,” followed by two interpretations by the Tannaim.[2] The Rambam, however, reads the opening line as a first, anonymous opinion, distinct from R. Yehuda and R. Shimon. The tanna kama states there is a prohibition on multiplying wives, with no distinction between righteous and wicked. Then R. Yehuda offers his reading, and R. Shimon offers another. Following standard rules of psak, the Rambam rules like the anonymous first view—hence his comment in the Commentary on the Mishnah that the halakhah is neither like R. Yehuda nor like R. Shimon. The practical upshot appears in the law cited above. Consistent with this, in his Fifth Principle the Rambam treats “rationale verses” as belonging to the explanatory plane, not the legal one (contra both R. Yehuda and R. Shimon). The Ramban saw this sugya as a difficulty for the Rambam; in truth, it is likely its source.

For our purposes: there is a three-way Tannaitic dispute about rationale-verses. According to R. Shimon, the “rationale” is actually an additional prohibition (not a rationale). According to R. Yehuda, it is indeed a rationale, but it is written so that we expound it (because generally we do not expound rationales) and derive legal consequences. The Ramban rules like him. Finally, according to the anonymous first view—followed by the Rambam—the rationale merely explains the command and has no legal ramifications. On all three views, the Bach is not vindicated: the rationale-verse is not written to teach that we must intend, but either to explain the mitzvah or to add specific legal detail. True, the case above concerns a prohibition and our case a positive command; but as I already noted, if in prohibitions the rationale merely explains the command, there is no reason—and certainly no necessity—to assume that in positive commands it serves a different purpose.

As an aside, this Tannaitic (and Rishonic) dispute reflects different conceptions of the very rule that we do not expound a verse’s rationale (that is, regarding ta’amei ha-mitzvot not explicit in the text). For R. Yehuda, we do not expound the rationale unless it is written; plainly this is because the non-expounding stems from concern that we might be wrong about the rationale. When it is explicit, we do expound it. On this approach, there is room for the Bach’s claim that when the rationale is explicit one must intend it. If this is the mitzvah’s purpose, it stands to reason that in performing it we should intend it and aim to realize it. Even so, as we have seen, this still does not follow—let alone necessarily—and certainly it is unlikely to be the only purpose. But for the anonymous first view, we do not expound the rationale even when explicit. That implies that non-expounding is not due to doubt about the rationale, but that even if it is the rationale, it has (and can have) no halakhic ramifications (we explained this in the article). If it is not the only rationale, I would still expect a demand to intend it during performance. But if the reason is that rationales cannot affect law—e.g., because the rationale will be realized automatically without intention (wearing Tzitzit will lead to remembering the commandments; dwelling in a sukkah will lead to remembering the Exodus)—then again there is no necessity to intend it explicitly when performing the mitzvah. I will now elaborate.

Nevertheless, the Bach: between command and expectation

We saw that according to the anonymous first view—and the Rambam who rules like it—the rationale-verse merely explains the law and has no halakhic implications. Still, there might be room for the Bach’s directive to intend at the time of performance, on the basis of reason: perhaps that is not what the verse comes to teach, but if this is indeed the mitzvah’s rationale, it makes sense that we should intend it. For example, if the purpose of Tzitzit is to remember the commandments, it seems most fitting that we actually remember the commandments when enwrapping—since that is the whole point. That would be true even absent an explicit command. And so, too, for remembering the Exodus when dwelling in the sukkah. We do not need an explicit command to infer that we ought to intend. And yet, as we will now see, even that inference is far from necessary.

First, I already noted that we would then have to do the same for mitzvot whose rationale is not stated. We would strive to discern their rationale and intend it. Even if we erred, at least it would be a laudable attempt, since the rationale is the mitzvah’s purpose. It is unclear why the Bach says this only about mitzvot whose rationale is explicit.

Second, we must distinguish between a geder (defining legal criterion) and a rationale. It may be that the Torah means that remembrance will occur of itself when I wear Tzitzit or dwell in a sukkah, without requiring explicit intention. The mitzvah will bring me to the described goal; that is its end and rationale; but that does not necessarily constitute a directive for my intention at the time of performance. In short: it may indeed be the mitzvah’s rationale, but not its defining legal criterion. We saw that according to the Rambam and the tanna kama we do not expound a rationale even when explicit. Perhaps this is the reason; and if so, then the Bach’s derasha—learning from the rationale-verse a duty to intend—does not escape that rule. Nonetheless, it is certainly fitting that if this is the mitzvah’s rationale one should intend it when performing the mitzvah, since the Torah stated that this is the goal; we ought to try to realize it in the best manner. But even if true, this is not a halakhic obligation. To turn it into one is, in effect, to expound a verse’s rationale.

More than that: grammatically, a rationale-verse is not an imperative but a declarative—stating a fact, not issuing a command. By definition, declarative verses are not mitzvot, as we see in several places in Hazal, e.g., “Wherever it says ‘beware,’ ‘lest,’ or ‘do not’—it is a prohibition” (Eruvin 96a and parallels). See also the beginning of the Rambam’s Eighth Principle and, at length, our article on that principle. Thus, if the Torah reveals to me that humility is a positive trait (e.g., “The man Moses was very humble …”), it is indeed proper to work on humility, but absent an imperative there is no halakhic duty. Only imperative verses generate halakhic obligations. Consider verses such as “You shall do what is right and good” or “You shall be holy” and others teaching virtues and proper conduct. These are not counted among the 613 because Hazal understood that despite their grammatical form, they are not legal imperatives. They express expectations rather than commands; and without a command, there is no halakhic obligation. I elaborated on this in my article on the halakhic standing of “theoretical reasoning.” If so, rationale-verses in Tzitzit, Tefillin, or Sukkah may well express the Torah’s expectation that we direct those special intentions—but they do not create a halakhic duty to intend. This may underlie the Pri Megadim’s ruling we saw above: it is proper to intend those intentions, but they do not invalidate.

The background assumption is that the stated rationale in these mitzvot is not the mitzvah itself and, in fact, is not a command at all (for it is a declarative verse), but rather the mitzvah’s end or perhaps only an accompanying intention. Even for the Bach, at most there is a mitzvah to remember the Exodus by dwelling in a sukkah, or to remember the commandments by wearing Tzitzit. On that definition these are not truly “rationales” of the mitzvah but part of the instruction for what to do—not only to dwell in a sukkah but to do so as a remembrance. On that understanding, the rationales of these mitzvot are something else entirely, achieved through the act and the intention together. As I argued above, even for the Bach it is reasonable that the act is not merely an instrument to achieve the intention (otherwise a sign would suffice), but that the act accompanied by intent jointly achieves some third aim.

In sum: In mitzvot to which the Torah appends a rationale-verse, it is surely fitting to intend that goal. But it is very unlikely that this constitutes a binding halakhic duty. This is no different from other non-binding directives outside of halakhah. In this sense there is no halakhic novelty in the Bach’s words; it is self-evident. If there is a verse, one should act in its spirit (and not treat it as an “uprooted verse,” in the previous column’s terms). If the Bach meant to innovate a legal requirement (even lekhathila but not me’akev)—I think he was not correct.

[1] It is disputed in the Gemara and among the decisors whether intent is essential (i.e., whether “mitzvot require intent”), but all agree one should intend.

[2] Indeed, in the Bava Metzia sugya the Mishnah’s wording is slightly different: “only up to eighteen” is not mentioned there, and only the verse itself appears. There it implies the opening line is merely a heading, not an additional Tannaic opinion. But in the Sanhedrin text of the Mishnah it certainly implies like the Rambam, not the Ramban. Interestingly, the Masoret HaShas on the margin in Sanhedrin notes several Tosafot that use this Mishnah as a representative example where R. Yehuda and R. Shimon dispute the tanna kama’s (i.e., the “heading’s”) meaning—Tosafot understood like the Ramban, that the heading is not a separate opinion.