The Talmud (Sukkah 38b) teaches that mitzvot that require speech can be fulfilled by listening to the speech of another, or “Shomea K’Oneh”. It would seem that this phrase could be translated in two ways: a) to listen is the same as to say; or b) the one who listens is the same as the one who is saying (shomea k’ha-oneh). The difference between these two is significant, and appears to be the basis of a dispute among authorities. The Mishnah (Megilah 24a) states that the maftir also had the honor of birkat kohanim. This is a difficult statement, as all eligible kohanim participate in birkat kohanim, and it is not a special honor given to one person. The Beit haLevi, in his work on the Torah, quotes an anonymous chacham as explaining that the mishnah refers to the practice of one kohen reciting the birkat kohanim, while the others fulfill their obligation via shomea k’oneh. The Beit haLevi denies that such a possibility exists, and asserts that shomea k’oneh is not a viable option for birkat kohanim. The popular interpretation of the Beit HaLevi’s position is that “Shomea K’Oneh” is as “to listen is the same as to say”. Thus, the method is effective in crediting the listener with speech. However, that is only sufficient if the mitzvah calls for nothing more than speech. If anything more than speech is required, that element will remain unfulfilled. In the case of birkat kohanim, the words must not only be recited, they must be pronounced “in a loud voice”. Shomea k’oneh will succeed in having the words considered spoken, but not in a “loud voice”. Such a position would create difficulties in some common instances of shomea k’oneh utilization. Kiddush must be recited over a cup of wine; how, then, can on fulfill Kiddush by listening to someone else, when the listener is without the cup of wine? It would, according to the above interpretation, be as if one is reciting the words of Kiddush empty-handed. The mitzvah of reading the megillah must be done out of a kosher megilah; those who listen, in synagogue, without a kosher megilah, would be considered as if they are reciting the words by heart. Thus, asserts the Chazon Ish (Orach Chaim 29), it is the second interpretation of shomea k’oneh that is correct: the one who listens is the same as the one who is saying. If the one actually saying the words is fulfilling all requirements, such as holding a cup of wine or utilizing a kosher megilah, the listener is credited with these as well. It should be noted, though, that several acharonim, including the Brisker Rav; Rav Yosef Dov Soloveichik; the Emek Brakhah; Rav Elazar Schach; and the Steipler Gaon, all disagreed with the above interpretation of the Beit haLevi. They instead suggest that he agrees that in such instances as megilah and Kiddush, the details of the performance transfer to the listener. His opinion was specific to birkat kohanim, where not only extra details are involved, but there is a need to communicate with others (in that case, the kohanim with the congregation). When there is a need to communicate with others, it is clearly insufficient to use a method of “speech” that is in actuality silent. Based on this perspective, some question whether other mitzvot that require not only speech but communication could be performed through shomea k’oneh, such as the recitation associated with eglah arufah (see Nachal Eitan, 15:2:11) and with chalitzah (see Resp. Har Tzvi O.C. 57). Whether or not the first version of the Beit HaLevi is accurate, it is the explicit view of R. Ya’akov Emden. In his Sh’eilat Ya’avetz (75) he argues on the position of the Taz (O.C. 141) who allows a blind man to receive an aliyah, even though the essential requirement of the one receiving an aliyah is to read the section of the Torah. In modern contexts, a “professional” is reading aloud at the same time, and the oleh, by listening to him, can “read” through shomea k’oneh, reasons the Taz. R. Emden disagrees; shomea k’oneh only works to make the listened word be considered as “spoken”; in this case, it would be as if the oleh is reciting the section by heart, which would be invalid. This issue appears to underlie a dispute among the rishonim. Rashi (Sukkah 38b) discusses the common situation of one who finds himself in the middle of the amidah while the congregation has already started kedushah. In his view, the best approach would be to pause and listen, thus “answering” kedushah through shomea k’oneh without actually interrupting the amidah. Tosafot (Berakhot 21b s.v. ad sh’lo yagea) argue, noting that this plan is counterproductive; since listening is the same as speaking, an interruption will by definition occur. Thus, Rashi seems to be assuming the second interpretation: shomea k’oneh allows one to join in the fulfillment of another, without actually speaking. Tosafot, on the other hand, is assuming the first position, that listening is identical to speaking. (The Shibolei haLeket represents a third opinion; see Sha’agat Aryeh, 6. See also Talmidei Rabbeinu Yonah, Berakhot 13b) The Rambam seems to reflect both opinions. In Hilkhot Berakhot (1:11) he writes that one who listens to the berakhah of another, with proper intent, fulfills his obligation. One who answers amen, though, is as if he had actually spoken the words of the berakhah. In considering the above possibilities, together with variations, three models of shomea k’oneh emerge: a) listening functions in a manner identical to speech, no more and no less (perhaps comparable to the law of “hirhur k’dibbur” (thought is like speech); see Bekhor Shor to Berakhot 54b, and note the question of R. Akiva Eiger in his tosafot to the mishnah); b) through some variation on shlichut (agency), despite some key differences, such as the fact that these mitzvot are performed physically (and would thus generally be excluded from shlichut), and the fact that shlichut normally would not require the presence of the appointer. The Kogaglover Rav (Siach HaSadeh, Sha’ar Birkhat Hashem, 4:4), expresses a very literal version of this model, and feels it explains many details of shomea k’oneh, such as the position of Tosafot (Berakhot 21b) that ideally one should recite a berakhah on his own (shlichut is also considered less preferred than performing a mitzvah one’s self); and c) a type of partnership between the speaker and the listener, that has some commonality with shlichut (see Resp. Chatam Sofer, O.C., 16, and Siach Yosef, 22).