The rabbinic prohibition only applies to those who clap their hands consciously.
Rabbi Yisrael Nissan Kupershtoch (1858-1930) grew up in the milieu of the Warka Hassidim in Poland. After his marriage, he traveled to his wife’s uncle, Rabbi Yehiel Dancyger (1828-1894), the founder of what would become the Aleksander Hassidic dynasty. Rabbi Kupershtoch served in the rabbinate in Poland, and in 1924 he left for the Land of Israel.
Many of his writings were lost, but after arriving in British Mandate Palestine, he published one volume of his legal writings: Responsa Ani Ben Pahma (Jerusalem 1928). In this collection, he recounts a fascinating episode that he witnessed in his youth.
As a young boy, he had studied under Rabbi Yisrael Eliyahu Yehoshua Trunk of Kutno (1820-1893) – a renowned halachic authority and a disciple of the Kotsker rebbe, Rabbi Menahem Mendel Morgensztern (1787-1859). Besides serving in the rabbinate in a number of Polish towns, Rabbi Trunk authored Yeshuot Yisrael (Warsaw 1870) – a work on the civil law section of the of the Jewish Code of Law – and Yavin Da’at (Piotrkow, 1932) on the ritual sections of the Code. In addition to Yavin Da’at, his responsa were published posthumously under the title Responsa Yeshuot Malko (Piotrkow, 1927-1939).
In a way, Rabbi Trunk represented the resolution of the enmity between the hassidic community and the opponents of hassidism, the Mitnagdim. His very name reflected that resolution: His parents gave him three names – Yisrael, after the person who inspired the hassidic movement, the famous Rabbi Yisrael Ba’al Shem Tov (c. 1700-1760); Eliyahu, after the highest rabbinic authority who opposed the nascent hassidic movement, Rabbi Eliyahu the Gaon of Vilna (1720-1797); and Yehoshua, after Rabbi Ya’acov Yehoshua Falk (1680-1756), the great talmudist and author of Pnei Yehoshua (Frankfurt-am- Main and Furth 1752-1780) – a commentary and novellae on the Talmud. Rabbi Trunk’s parents, it appears, blessed their son with straddling more than one world.
Rabbi Kupershtoch described how he sat as a young boy at Rabbi Trunk’s Shabbat table, and Rabbi Trunk would often cry out in excitement, “Master of the universe!” – first in Aramaic and then in the Yiddish vernacular. And he would be moved to clap his hands animatedly.
One particular Shabbat, this conduct apparently irked one of the guests, as Rabbi Kupershtoch reported: “And there was one person – an extremely learned and God-fearing person… who heard the sound and [saw] the clapping of the hands and he bent down and whispered the following in the holy ears [of R. Trunk]: Master, does it not say that we do not clap?'”
The guest – who, according to Rabbi Kupershtoch, was not of the hassidic ilk – was referring to the Mishna that rules that we do not dance, clap, or drum a beat on our thigh on Shabbat and festivals (M. Beitza 5:2). The Talmud explains that this prohibition is a rabbinic enactment to ensure that we do not repair musical instruments while in the ecstatic mode of moving to the rhythm of music (B. Beitza 36b). This position was accepted as normative law, save on the festival of Simhat Torah, when a special license to dance was granted (Shulhan Aruch OH 339:3). Thus the guest was wondering how his esteemed host, a recognized halachic authority, could blatantly contravene Jewish law.
Rabbi Trunk’s response – as recorded by Rabbi Kupershtoch – was surprising: “Oh, they clap by themselves, they clap by themselves, and there is no [transgression of a] prohibition, Heaven forfend.”
Rabbi Trunk did not clearly spell out why he felt that his clapping was permitted, but writing many years later, his student elucidated the master’s meaning: “Because his heart was aroused, his limbs were aroused to movement to clap hands. Certainly he did not transgress a rabbinic prohibition with this.”
Rabbi Kupershtoch continued to explain that when one is enthusiastically serving the Almighty, he may clap his hands, given that he has no conscious intention to do so. The rabbinic prohibition only applies to those who clap their hands consciously. In the case of Rabbi Trunk, his hands were clapping of their own accord as a result of his passionate and unbridled Shabbat enthusiasm.