The Mitzva of Kri'at Shema and Talmud Torah
The twice daily mitzva of kri'at shema is defined as a declaration of basic tenets of belief, a twice daily kabbalat ol malkhut shamayim (acceptance of the yoke of the kingdom of heaven). The themes of shema range from yichud Hashem (Gods exclusivity as well as indivisibility), ahavat Hashem (loving God), talmud Torah (Torah study), mitzva acceptance, and recognizing Divine intervention, as first witnessed during yetziat Mitzrayim. In theory, this declaration and elaboration could have been accomplished through a personal text. However, since the Torah states, "ve-hayu ha-devarim ha-eileh" that these words, referring to the Torah portions of shema are to be on our hearts, we recite the Torahs formulation.
In fact, the gemara in Berakhot (14b) records that one Amora did not recite the third parasha (taken from Parashat Shelach), but instead included a personal text to discuss yetziat Mitzrayim. Although we do not accept his position and even his creativity was feasible only regarding the third paragraph of shema his view points to the fact that the essence of shema is a theological assertion or declaration. This declaration may be halakhically structured around Torah texts, but the mitzva is defined as kabbalat ol malkhut shamayim.
An interesting gemara in Menachot evokes a different model of the mitzva. The gemara (99) discusses the parameters of talmud Torah and claims that even if a person only recites shema in the morning and evening, he has still fulfilled the mitzva. An interesting debate emerges between R. Shimon bar Yochai, who cautions against publicizing this loophole, and Rava, who encourages it. Obviously, there is merit to each position: broadcasting would lower the standard and deter more intense commitment, but it would also affirm lesser achievements in Torah and there is nothing like validation as a motivating factor! Regardless of which social policy is endorsed, all opinions believe that shema recital qualifies as daily Torah learning.
However, this conclusion DOES NOT assert that the mitzva of kri'at shema is DEFINED as Torah study. Rather, it asserts that INCIDENTAL to the performance of kri'at shema, Torah is BEING STUDIED. Since the shema mandates reading actual Torah portions, the outcome of shema performance is Torah study.
A similar conclusion may be drawn from an interesting mishna in Berakhot (9b), which limits morning kri'at shema recital to the first 3 hours of the day. The mishna comments that "after this period, if shema is recited, it is not worse than general Torah study." The mishna's consolation is certainly true Torah verses have been recited, even though shema period has elapsed but it seems too obvious to merit inclusion. What deeper point is alluded to by this otherwise obvious assertion?
One approach suggests that this mishna views kri'at shema as a Torah legislated moment of Torah study. The theological elements of Judaism (kabbalat ol malkhut shamayim) should be embraced specifically through the STUDY OF THE TORAH SECTIONS that enumerate these ideas. Accordingly, Torah study is not INCIDENTAL to shema recital; rather, fulfillment of the mitzva of shema entails reading PARTICULAR Torah sections DURING PARTICULAR time periods. Discussing someone who neglected THIS type of Torah-based mitzva, the mishna still consoles that he has still fulfilled the GENERAL unregulated (by time or content) mitzva of Torah study. If this is indeed the inference of the mishna in Berakhot (9b), we have located the first source that may identify Torah study as the definition of the mitzva of shema.
This approach would explain a difficulty posed by another gemara. The gemara in Shabbat records that R. Shimon bar Yochai exempted himself from kri'at shema because he was immersed in Torah study. This position is difficult, as Torah study does not exempt one from ANY mitzva performance and should not override the mitzva of shema. The gemara's only solution is to highlight that for R. Shimon bar Yochai, "torato umnato" his Torah is his profession. In effect, the Bavli seems to extend a universal mitzva exemption to someone who exclusively and exhaustively studies Torah, at least according to Rebbi Shimon bar Yochai.
The Yerushalmi's strategy for explaining R. Shimon bar Yochais behavior is quite different. Defending this exemption, the Yerushalmi reasons: "This [shema] is study, and this [actual torah study] is study. Since R. Shimon is already involved in study, he is exempt from a different STUDY-based obligation namely, shema. This is a radically different approach. Evidently, the mitzva of shema is defined as Torah study that yields kabbalat ol malkhut shamayim. Since shema is executed by studying Torah, it does not obligate those who are already studying Torah (at least according to R. Shimon). Keep in mind that according to the Yerushalmi, ONLY shema is exempted, NOT OTHER mitzvot, as they are not defined as Torah study.
This rationale in the Yerushalmi is perhaps the clearest assertion that the mitzva of shema does not incidentally yield Torah study, but is rather defined as Torah study. If Torah study were the incidental yield of shema but not its core definition, it would override Torah study in the same way that all other mitzvot override Torah study.
A second indication that the mitzva of shema is defined as Torah study may stem from a different Yerushalmi. The Bavli (11b), while discussing the berakhot recited before Torah study, mentions that the berakha of Ahava Rabba (recited prior to shema) may qualify as a birkhat ha-Torah. If the standard berakhot were not yet recited and shema was already recited, no additional berakhot should be performed, since Ahava Rabba suffices. Thematically, this is logical, since the berakha of Ahava Rabba covers most of the themes of the birkhot ha-Torah. The Yerushalmi conditions this halakha upon the fact that some ACTUAL Torah is studied immediately. Practically, the berakha of Ahava Rabba can only serve as birkhat ha-mitzva if Torah is studied immediately after Shemoneh Esrei. (Prior to Shemoneh Esrei, unrelated Torah study would entail a disruption [hefsek] in the tefila.)
Interestingly, Tosafot in Berakhot (11b) assume that this requirement applies to ALL birkhot ha-Torah, even the standard ones; they must be followed with some actual Torah study. This serves as the source for reciting select Torah sections after birkhot ha-Torah in our morning tefila (Birkhat Kohanim and the mishna in Pe'ah known as Eilu Devarim). According to Tosafot, the Yerushalmi is qualifying birkhot ha-Torah IN GENERAL and not addressing Ahava Rabba in particular.
However, many Rishonim (including independent Tosafists, such as Rabbenu Yehuda Ha-Chasid) believe that the Yerushalmi is specifically referring to Ahava Rabba. General birkhot ha-Torah DO NOT require immediate learning; however, Ahava Rabba can only function as a birkhat ha-Torah if it is accompanied by immediate learning, as it references Torah study only indirectly.
This qualification makes eminent sense, but for some reason, the Bavli does not impose this condition. The Bavli evidently believed that Ahava Rabba can function as a birkhat ha-Torah even without immediate Torah study following its recital.
Theoretically, the Bavli may have disagreed with the Yerushalmi's premise that Ahava Rabba is too abstract to serve as birkhat ha-Torah without actual torah study following. Perhaps the disagreement revolved around the syntax of the liturgy and whether it is direct enough to stand in as a berakha or as a birkhat ha-Torah. If this is the case, there is no ramification here for the nature of the mitzva of shema.
However, the Bavli/Yerushalmi debate may have surrounded the nature of the mitzva of shema. According to this approach, all agree that Ahava Rabba is too abstract to be considered a birkhat ha-Torah without immediate Torah study. The Yerushalmi therefore demanded ACTUAL study; the Bavli claimed that shema recital qualifies as Torah study, since the mitzva is structured as Torah study. Since Ahava Rabba is naturally followed by Torah study in the form of shema, it constitutes a halakhic birkhat ha-Torah.
A final expression of shema as a mitzva of Torah study can be detected in an interesting comment of the Meiri. The gemara in Berakhot 13a (as well as several parallel gemarot) cites a dispute between R. Yehuda, who required shema recital in Hebrew, and the Rabbanan, who allowed it in any language. Initially, the gemara assumes that the halakha regarding the language in which shema should be recited teaches us something about the proper language of "kol ha-Torah kula." Thus, the fact that the Rabbanan learned that shema may be recited in any language from a gezeirat ha-katuv indicates that kol ha-Torah kula must be recited in Hebrew; otherwise, there would be no need for a special pasuk to indicate the halakha regarding shema. Similar logic comparing and contrasting shema to "kol ha-Torah kula" is developed within R. Yehuda's position. It is unclear from the gemara what the phrase "kol ha-Torah kula" actually refers to and what type of precedent it sets for shema recital.
The Meiri claims that the gemara was comparing and contrasting shema recital to Torah learning. What can be inferred from this dispute regarding shema to the language of talmud Torah? Must the mitzva of talmud Torah be performed in Hebrew (loyal to its original delivery), or does any language suffice (since its activity is primarily cognitive)? Although no gemara directly addresses this question, the gemara wanted to extrapolate this idea from the debate about shema and language. Since shema is effectively Torah study, its language reflects something about the language of general Torah study; the gemara is simply unsure of whether that reflection is direct or inverted. In other words, should shema's language be consistent with general Torah study, or, given the need for a special pasuk to determine shema's language, should it be inconsistent with the language of general Torah study? Either way, shema is seen as primarily structured around Torah study, and its language will help determine in one way or another the language of torah study.
To summarize there are three gemarot which strongly suggest that the mitzva of shema is not merely performed by declaring theological principles through reciting Torah portions, but rather by engaging in Torah study of these portions. R. Shimon bar Yochai exempted himself from shema because he was studying Torah and he reckoned that this excused him from the Torah study of shema; the Bavli did not require immediate Torah study after reciting Ahava Rabba, perhaps because shema recital filled that role; and according to the Meiri, the determined language of shema may help us uncover the required language (if any) of Torah study.
Having established the possibility that shema is based upon specific Torah study and not mere theological declaration, we may inspect an interesting phenomenon in the Rambam's list of mitzvot. He lists "belief in the unity of God" as the 4th mitzva and the mitzva of shema as the 10th mitzva. On the surface, these mitzvot would seem to overlap and do not justify separate listing. Isn't shema the mitzva to affirm the unity of God, and thus already subsumed under that mitzva? A technical solution may be to divide between the mitzva to BELIEVE (mitzva #4) and the mitzva to verbally declare (mitzva #10). Alternatively, given the aforementioned option of viewing shema as a mitzva to study Torah, perhaps a different solution can be raised. The 4th mitzva is to believe in Hashem's unity. Shema, however, does not constitute merely internal belief or even verbal articulation, but an act of Torah study centered around theological principles. It is therefore independent of the purely theological mitzva of belief and is listed independently.