The Rambam on Biblical Shekels and Rabbinic Currency

How the Rambam codifies the ancient weight of the biblical sela and reconciles the Sages' currency additions with Sanctuary valuations.

The Fluctuating Standard of the Holy Shekel

The Gemara investigates the exact value of biblical monetary obligations. Rava states that the original biblical סֶלַע (sela) weighed three and one-third דינרים (dinars). The Torah defines the shekel as twenty גֵּרָה (gerah), and translation equates gerah to מעה (ma'a). Since six silver ma'ot make a dinar, twenty ma'ot yield only three and one-third dinars.

The Gemara challenges this from Sanctuary valuations, where an ancestral field is redeemed at fifty selaim over forty-nine years. The Sages ruled that one pays a sela and a פונדיון (pundeyon, half a ma'a) per year. That calculation assumes a Sanctuary sela consists of forty-eight pundeyonim, or four full dinars. The Gemara resolves this by explaining that the Sages added one-sixth to the original shekel.

בָּתַר דְּאוֹסִיפוּ עִילָּוַיְיהוּ, דְּתַנְיָא: ״עֶשְׂרִים גֵּרָה הַשֶּׁקֶל״ — לָמַדְנוּ לַשֶּׁקֶל שֶׁהוּא עֶשְׂרִים גֵּרָה, וּמִנַּיִן שֶׁאִם רָצָה לְהוֹסִיף יוֹסִיף? תַּלְמוּד לוֹמַר: ״יִהְיֶה״

After they added to them. As it is taught: 'Twenty gerah shall be the shekel'—we learned for the shekel that it is twenty gerah; and from where is it derived that if one wishes to add, he may add? Scripture teaches: 'shall be' (yihyeh). (Bekhorot 50a:6)

The Rambam's Definitive Breakdown of Denominations

The Rambam codifies the enlarged Second Temple standard across the Mishneh Torah. He explains that the biblical shekel is the talmudic sela, while the biblical gerah is the rabbinic ma'a. After the rabbinic enlargement, every sela equals four silver dinars.

Each dinar contains six ma'ot, establishing the sela at twenty-four ma'ot. Each ma'a divides into two pundeyonim, each pundeyon into two איסרין (issarin), and each issar into eight פרוטות (perutot). In absolute silver weight, the Rambam fixes the ma'a at sixteen barleycorns and the perutah at half a barleycorn.

הַסֶּלַע אַרְבָּעָה דִּינָרִין וְהַדִּינָר שֵׁשׁ מָעִין. וּמָעָה הִיא הַנִּקְרֵאת בִּימֵי משֶׁה רַבֵּנוּ גֵּרָה. וּמָעָה הִיא שְׁנֵי פּוּנְדְיוֹנִין וּפוּנְדְיוֹן שְׁנֵי אִיסָרִין. וּפְרוּטָה אַחַת מִשְּׁמוֹנָה בְּאִיסָר.

A sela is four dinarim, a dinar is six ma'ah, and a ma'ah was called a gerah in the time of Moses our teacher. A ma'ah equals two pundeyonim, and a pundeyon is two issarin. A perutah is one-eighth of an issar. (Mishneh Torah, Sheqel Dues 1:3)

Resolving the Ancestral Field Surcharge

In the laws of valuations, the Rambam applies this exact currency breakdown to ancestral field redemptions. When redeeming an ancestral field over forty-nine years, the fixed Torah cost is fifty selaim. Divided across forty-nine years, the annual rate equals one sela and one pundeyon.

This formula presents an arithmetic difficulty: forty-nine pundeyonim equal one sela and one pundeyon over the fifty selaim. The Rambam explains that this extra coin reflects commercial realities. A money-changer charges forty-nine pundeyonim to deliver a whole sela. The Kessef Mishneh confirms that the Rambam takes this rule directly from our sugya in Bekhorot.

נִמְצָא לְכָל שָׁנָה סֶלַע וּפוּנְדְיוֹן. שֶׁאַף עַל פִּי שֶׁהַסֶּלַע שְׁמוֹנָה וְאַרְבָּעִים פּוּנְדְיוֹנִין. כְּשֶׁיִּתֵּן פּוּנְדְיוֹנוֹת לִקַּח סֶלַע מִן הַשֻּׁלְחָנִי נוֹתֵן תִּשְׁעָה וְאַרְבָּעִים:

Thus for each year it is a sela and a pundeyon. For even though a sela is forty-eight pundeyonim, when one gives pundeyonim to obtain a sela from a money-changer, he gives forty-nine. (Mishneh Torah, Appraisals and Devoted Property 4:3)

Biblical Authority for Expanding Sacred Dues

The commentators analyze how the Sages had authority to augment biblical payments. Kiryat Sefer notes that the Torah explicitly wrote 'shall be' regarding valuations. This biblical phrasing teaches that another state with an increase remains fully valid under the definition of a shekel.

The Kessef Mishneh notes that the word 'it is' forbids any reduction below twenty gerah. Thus, the Sages could enlarge the shekel to match Tyrian currency, but could never diminish it. Even Ha'azel explains that this principle applies across all statutory Torah obligations, including penalties paid by a rapist and seducer.

דכתיב גבי ערכין עשרים גרה יהיה השקל ודרשינן מנין שאם רצה להוסיף עליו מוסיף ת"ל יהיה דמשמע עוד הויה אחרת בתוספת מיקרי שקל.

For it is written regarding valuations: 'Twenty gerah shall be the shekel,' and we expound: From where do we derive that if one wishes to add to it, he may add? Scripture teaches: 'shall be' (yihyeh), which implies another existence with an increase is still called a shekel. (Kiryat Sefer on Mishneh Torah, Appraisals and Devoted Property 4:3:1)

Practical Implications for Torah and Rabbinic Obligations

In practice, every set monetary amount specified by the Torah is paid exclusively in high-grade Tyrian silver. This includes the five selaim for פדיון הבן (pidyon haben, redemption of the firstborn son), which require twenty full dinars. By contrast, payments established by rabbinic law are evaluated in כסף מדינה (provincial currency).

Provincial currency contains merely one part silver to seven parts copper. Consequently, a rabbinic penalty of one sela requires only one-half of a silver dinar. The Rambam ensures that while rabbinic penalties remain modest, sacred Torah commitments are always discharged according to the augmented Sanctuary weight.

The Rambam permanently sets all statutory Torah silver payments to the enlarged Tyrian standard of twenty-four ma'ot per sela, while rabbinic assessments are discharged in provincial coin.

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