In describing the festival of Rosh Hashannah, the Torah employs two very different epithets. In Parshas Pinchas (Bamidbar 29:1), the day is dubbed a "Yom Teruah" (a day of blowing), while in Parshas Emor (Vayikra 23:24), it is referred to as a "Zichron Teruah" (a remembrance of blowing). While the Gemarah (Rosh Hashannah 29b) initially assumes that "Yom Teruah" refers to Rosh Hashannah that falls on a weekday (hence the active "day" of blowing) and "Zichron Teruah" refers to Rosh Hashannah that coincides with Shabbos (on which shofar is not blown; hence the mere "remembrance" of blowing), the Gemarah ultimately concludes that the disparity of language does not actually teach the abstention from shofar blowing on the Shabbos. Rather, the cancellation of shofar blowing on Shabbos is a function of a Rabbinic - not Biblical - injunction, enacted out of fear that one might come to carry a shofar in a reshus haRabim.[1] In coming to this conclusion, however, the Gemarah makes no mention of what the disparity of language - "Yom Teruah" versus "Zichron Teruah" - comes to teach us.
To account for this discrepancy, Rav Soloveitchik Zt'l suggested that perhaps the Torah is highlighting two components of the mitzvah of tekiyas shofar. While the action of the mitzvah ("ma'aseh mitzvah") is accomplished through merely blowing the shofar (signified through "Yom Teruah"), the mere action of blowing, by itself, is insufficient. The ultimate fulfillment and completion of the mitzvah ("kiyum mitzvah") occurs internally, through an emotional recognition of the shofar's message (signified through the internally-focused "Zichron Teruah"). In most mitzvos, the "ma'aseh mitzvah" and the "kiyum mitzvah" occur simultaneously. The very moment one performs the action of eating matzah, for example, one instantly completes the "kiyum mitzvah" as well. However, with shofar, the action does not represent an end in and of itself, but rather a means of triggering an emotional response. It is this emotional response, the "kiyum She'Ba'Lev" epitomized by the notion of "Zichron Teruah," which constitutes the essence of the mitzvah.[2]
This distinction, between the action of blowing the shofar and the true fulfillment of the subsequent emotional recognition, may help explain an apparent contradiction in the Rambam. In Hilchos Shofar, 2:4, the Rambam rules that if one does not have appropriate intent ("kavannah"), he does not fulfill the mitzvah of shofar. In Hilchos Chametz U'Matzah, 6:3, however, the Rambam appears to give the exact opposite ruling: if one eats matzah under duress, without intent to fulfill his obligation, he nonetheless fulfills his obligation. The Rambam's understanding of whether or not mitzvos require intent is thus obfuscated by apparently contradictory rulings in Hilchos Shofar and Hilchos Chametz U'Matzah. Rav Soloveitchik Zt'l, suggested that perhaps there is no contradiction whatsoever. A mitzvah's subjection to the general requirement for "kavannah" is a function of the nature of the particular mitzvah. Mitzvos like matzah, in which the "ma'aseh mitzvah" and "kiyum mitzvah" are inseparable, do not require kavannah. Their action speaks for itself. Mitzvos like shofar, however, where the action is not an end in and of itself, but rather a means towards an internal "kiyum She'Ba'Lev" do require kavannah.[3] Hence, if one lacks kavannah during tekiyas shofar, he has not fulfilled his obligation.
Shofar's emphasis on a "kiyum She'Ba'Lev" may also manifest itself in several relevant halachos which underscore an inextricable link between the mitzvah of shofar and the mitzvah of tefillah, the prototypical "Avodah She'Ba'Lev" (service of the heart)[4]. For example, the Ba'al HaMaor (Rosh Hashannah 10b b'dapei haRif) assumes that the berachos which we recite before the blowing of shofar are a relatively recent innovation. In the times of the Gemarah, he argues, shofar was not blown before beginning Mussaf, as is common practice nowadays. The Ba'al HaMaor wonders: if shofar was only blown during and after the Tefillas Mussaf, when was the Birchas Hamitzvah (blessing generally recited prior to performing a mitzvah) for shofar blowing recited? He suggests that perhaps, the very text of Tefillas Mussaf itself, into which shofar blasts were inserted, served as a Birchas Hamitzvah[5]. Apparently, even though Tefillas Mussaf does not structurally resemble a classic Birchas Hamitzvah, the conceptual relationship between the kiyum She'Ba'Lev of shofar to the Avodah She'Ba'Lev of tefillah allows Mussaf to serve as a Birchas Hamitzvah.
This relationship is further highlighted by the Gemarah later in Rosh Hashannah (26b), which instructs that a shofar should be bent. Rashi, based on the Gemarah, explains that a bent shofar resembles a person bent in humility and submission during tefillah. Apparently, the shofar fulfills a role strikingly similar to that of tefillah. Moreover, the Gemarah on 26a develops this relationship in its discussion of "ain kateigor na'aseh saneigor." A shofar may not come from a cow, because that resembles the eigel hazahav, a memory which we do not wish to evoke. The Gemarah challenges this ruling, noting that the evocative problem of "ain kateigor" is seemingly only applicable to "avodos shebifnim" - services of the highest level of sanctity which take place in the Kodesh HaKodashim (such as selected parts of the Kohen Gadol's Yom Kippur service). However, shofar, which is not blown specifically in the Kodesh HaKodashim, should not be included in this restriction. The Gemarah answers that, since shofar serves as a "Zikaron" (commemoration), it is "k'lifnim dami" - as though it takes place in the Kodesh HaKodashim, and thus equally subject to restrictions of "Ain Kateigor…" Apparently, shofar's kiyum she'ba'lev makes it similar to the service of the Kohen Gadol on Yom Kippur, and by extension, to tefillah, which is directed towards the Kodash HaKodashim as well[6].
Shofar's subjection to the possibility of "mitzvah haBa'ah b'averiah" (a mitzvah fulfilled through a transgression) may also underscore shofar's special kiyum she'ba'lev. Based on the Yerushalmi, the Rambam (Shofar 1:3) rules that shofar is not subject to the problem of mitzvah haba'ah b'aveirah, because an intangible shofar blast cannot be stolen[7]. This technical reasoning implies that theoretically, shofar should be subject to mitzvah HaBa'ah B'Aveirah, and that its exemption is simply the result of a technical loophole. This implication is telling, however, since several Rishonim[8] opine that not all mitzvos are subject to mitzvah haba'ah b'aveirah. Mitzvah haba'ah b'aveirah only applies to supplicatory mitzvos, mitzvos which come "l'ratzos." If this is the case, apparently one must assume that shofar too is a mitzvah whose aim is to supplicate and to beg, much like prayer, and would thus be subject to mitzvah haba'ah b'aveirah if not for a technical solution.
Finally, the Rav Zt'l also pointed to the Gemarah in Rosh Hashannah 34b as a support to shofar's essential relationship to tefillah. If an individual has the option to spend Rosh Hashannah in a city where shofar will be blown but tefillah will not be recited, or in a city which will recite tefillah but not blow shofar, which is preferable? The Gemarah answers that obviously, the Biblical mitzvah of shofar would take precedence over the Rabbinical mitzvah of tefillah (the Gemarah concludes that even the mere possibility of shofar blowing would take precedence over a definite tefillah). The Rav, however, questioned the Gemarah's assumption that tefillah is simply a Rabbinic mitzvah. After all, numerous sources seem to suggest that Malchiyos, Shofros, and Zichronos on Rosh Hashannah might actually be a Biblical commandment as well[9]. If so, would this Gemarah not prove the contrary? The Rav suggested that perhaps, Rosh Hashannah's Mussaf tefillah may indeed be Biblical, but only when shofar is blown during services. If the tefillah is not accompanied by shofar blowing (as was the case in this Gemarah), however, then everyone would agree that the tefillah is simply a fulfillment on a Rabbinic level.
[1]Interestingly, the Talmud Yerushalmi concludes that the abstention from shofar on Shabbos is indeed a Biblical commandment, derived from the aforementioned verses.
[2]It should be noted that shofar is not the only mitzvah in which the action of the mitzvah is separated from the fulfillment of the mitzvah. tefillah (see Rambam tefillah 1:1), Simchas Yom Tov (see Pesachim 109a), Aveilus / Aninus (see top of Sanhedrin 46b) are all examples of mitzvos which prescribe specific actions which are means towards a desired emotional state.
[3]See Kesef Mishnah and Maggid Mishnah on Rambam ibid. This explanation may also be consistent with Rambam's general understanding of shofar, underscoring the passive listening as opposed to active blowing.
[4] See Ta'anis 2a.
[5]See Rosh, beginning of Maseches Berachos, who cites Rav Amram Gaon as saying a similar idea regarding Keriyas Shema and its berachos.
[6] See Berachos 30a.
[7] See Ra'avad, who quotes a different possibility.
[8]See Ritva Sukkah 9a, who quotes the Ba'alei Tosafos
[9]See, for example, Rashi Vayikra 23.