Bar-Ilan University
Parashat Pekudei 5771/ March 5, 2011
Parashat Hashavua Study Center
Lectures on the weekly Torah reading by the faculty of Bar-Ilan University in Ramat Gan,
Israel. A project of the Faculty of Jewish Studies, Paul and Helene Shulman Basic Jewish
Studies Center, and the Office of the Campus Rabbi. Published on the Internet under
the sponsorship of Bar-Ilan University's International Center for Jewish Identity.
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comments
to:
Dr.
Isaac
Gottlieb,
Department
of
Bible,
gottlii@mail.biu.ac.il
Uri Cohen
Tel Aviv
The Weight of the Ark Cover
Great commentators, thinkers, and scholars1 have dealt with the passages concerning
the weight of the Tabernacle's furnishing that were made of gold or plated with gold.
Since gold is one of the heavier metals in the world (its specific weight is 19.3
grams/cubic centimeter),2 the weight of the ark cover, which was made of pure gold,
arouses surprise and amazement.
This week's reading notes the length and width of the ark cover, but does not mention
its thickness: "He made a cover of pure gold, two and a half cubits long and a cubit
and a half wide" (Ex. 37:6).3 The Babylonian Talmud (Sukkah 5a) concludes that it was
1
This article is based on my book, KEM"AH (Kedushatam Mishkalam Hozkam) KLEI HAMISHKAN [The Vessels of the Sanctuary], Tel Aviv 2008. Many contemporary scholars as well
have dealt with this question (Profs. A.J. Greenfield, N. Aviezer, J. Spiegel; Rabbi Raphael
Hajbi), however they do not solve the problem of the enormous weight of the ark cover, rather
they further aggravate it (see in greater detail in my book, p. 132f.).
2
For the sake of comparison, iron = 7.8 gr/cm3; copper = 8.9; silver = 10.1; gold = 19.3.
3
Exodus 37:6. Likewise in Parashat Terumah (Ex. 25:17): "You shall make a cover of pure gold,
two and a half cubits long and a cubit and a half wide."
1
one span thick, thus providing us the missing information. Even if we use the
smallest possible equivalents for a cubit and a span (one cubit = 44 cm. one span =
7.33 cm.),4 we come up with a volume for the ark cover of 53,215 cubic centimeters.5
Multiplying this volume by the specific weight of gold, we come up with the ark cover
weighing 1027 kg., i.e., more than one ton of gold: 110 x 66 x 7.33 x 0.0193 = 1027
kilograms.
The Talmud cites the thickness of the ark cover not merely as a theoretical matter, but
as a concrete practical measure that should be taken literally, since the Talmud (loc.
sit.) uses this figure as the basis for the halakhic ruling that the minimum height of a
sukkah must be ten spans. Hence we are not at liberty to reduce the thickness of the
span set by the Sages. This measurement raises several questions and puzzling issues.
A) Could the ark cover alone, without the remaining implements and furnishings
associated with the ark, possibly have weighed 1027 kilograms? Simple and precise
computations yield a total weight for the ark, its contents, and all its component
parts – the ark cover, two cherubs, four rings, interior and exterior gold leaf on the
ark, the poles (for lifting the ark) and the wooden box – of 2,500 kilograms (2.5
tons).6
Our wonderment increases further when we consider the tradition that the ark was
carried by no more than four priests; i.e., each one would have been carrying more
than half a ton, on the average. Could there have been more than four priests
carrying the ark? Let us examine several sources:
1. Menahot 98b:
How do we know that the poles were placed along the width of the ark?
Perhaps they went along the length? Rabbi Judah said: two people cannot
walk when they are only a cubit and a half apart. And how do we know that
the ark was carried by four people? For it is written: "Then the Kohathites …
would set out" = two, and "who carried the sacred objects" (Num. 2=10:21) =
two.
2. Rashi (on Ex.25:12): "So that the two people carrying the ark could walk
between them" (between the poles).
4
These are the minimal dimensions, both according to Greenfield and according to N. Aviezer,
in their article in the Weekly Torah Study on Parashat Terumah (no. 642), in contrast to
Maimonides, who sets a cubit = 45.6 cm.; the Shulhan Arukh, 54 cm.; Hatam Sofer, 62.4 cm.,
and other opinions.
5
"Two and a half cubits long" = 110 cm.; "a cubit and a half wide" = 66 cm.; one span = 7.33
cm.
6
The total weight is from a precise computation appearing in my book and cannot be detailed
here.
2
3. The author of Minhat Hinukh writes in Commandment 95: "Two people would
walk on one side and two on the other … so that it was carried by four people,
two on one side and two on the other." Moreover, one cannot counter this
tradition by arguing, for example, that the ark was carried by more than four
people, since that would raise the question of how the commandment of
carrying the ark could have been implemented given that the halakhah required
the priests in front to walk backwards,7 so that they would not be with their
backs to the ark.
B) How are we to cope with the logical problem of the weight of the ark cover alone
being 1027 kilograms of gold, while all the gold in the Tabernacle and all its
furnishing came to no more than 1228 kilograms? For it says in Scripture, "All the
gold that was used for the work … came to 29 talents and 730 shekels by the
sanctuary weight" (Ex. 38:24). It has been established that a talent = 42 kilograms,
and a shekel = 14 grams. So, if we multiply 29 talents by 42, we come up with 1218
kilograms; and if we multiply 730 shekel by 14 grams, we come up with 10
kilograms; all in all, we have a total of 1,228 kilograms.
The solution is ostensibly quite simple, for there is a tradition in the Talmud that
"the ark bore those who carried it" (Sotah 35a); hence it made no difference what
was the total weight of the ark. However, the problematic nature of this statement
can be seen from the disagreements among the finest of Jewish commentators
throughout the generations as to the dimensions and shape of the Tabernacle's
furnishings.
1. Why did the Sages, as well as the geonim, bother discussing the measurements
of the Tabernacles if everything involved with it was miraculous? One could
simply set a uniform measure, even if it was illogical, and say that everything
was a miracle.
2. The question becomes all the more poignant when we note that certain rabbis
contradicted others, saying, "It does not stand to reason" (Ralbag, below); "We
think this should be emended" (Tashbetz, below) and others.
3. Why were there commentators who from the outset deliberately refused to
express an opinion lest "anyone who knows even a little engineering" might
refute what they said (Ralbag, below)?
4. If the ark "bore those who carried it," why was it placed on a cart in the days of
David, as we read in Scripture, "They loaded the Ark of G-d onto a new cart and
conveyed it from the house of Abinadab, which was on the hill; and Abinadab's
sons, Uzza and Ahio, guided the new cart" (II Sam. 6:3)? If it indeed carried its
bearers, they could have borne it themselves.
7
Cf. Numbers Rabbah 5.8, as well as the midrash commentaries of Hiddushei Radal and
Shmuel Strashoon, loc. sit.; Maimonides, Hilkhot Klei ha-Mikdash, 2.13.
3
5. Would it not be better to assume that this comment of the Sages stemmed from
the fact that the weight of the ark was so great that they wondered how a mere
four priests could have carried it on their own?
6. If the "ark bore those who carried it," why the poles and rings on the ark? Does
it not say, "then insert the poles into the rings on the side walls of the ark, for
carrying the ark" (Ex. 25:14)?
7. Some of the Tosaphists Bible commentaries8 wondered about the Sages'
statement that the "ark bore those who carried it": "The ark ought to have been
made entirely of gold [and not gold leaf], except that it had to be carried on the
shoulder and that would have made it too heavy." Further on they show
awareness of the issue at hand and ask, "even though it says that it bore those
who carried it?" The explanation they offer is that "it was temporary,"
apparently meaning that the miraculous occurrence applied only to the crossing
of the Jordan, when the Israelites entered Canaan.
We can see that several commentators were uneasy dealing with certain dimensions
of the Tabernacle's furnishings, witness this comment of Ralbag (on Ex. 25:11):
The thickness of the gold cases is unknown, nevertheless they must have had
tangible thickness so that they could exist; but it does not stand to reason
that the gold was one span thick,9 because it could not be that one of the
cases could have been completed in this thickness using the total quantity of
gold mentioned in Eleh Pekudei (Ex. 37:24), and this will be clear to anyone
who knows even a little engineering.
Proposed Solution
A way of solving the problem of the unreasonably huge weight of the ark cover is presented
in the Long Commentary of Ibn Ezra on the verse, "All the gold that was used for the work, in
all the work of the sanctuary" (Ex. 38:24): "The gaon (=Sa`adiah Gaon) said … the lampstand
was made of one talent of gold, likewise the ark cover, … and the ark cover was of solid
gold, and by received tradition from our ancestors it was made of one talent because it was
both long and wide." Thus, according to Ibn Ezra, who sites Sa`adiah Gaon, the ark cover
only weighed "one talent," i.e., 42 kilograms. If so, a rough computation shows that its walls
must have been approximately 2.5mm (which is about 5 times as thick as the metal sheet
used in automobiles).
How can this tradition be reconciled with the Talmudic tradition that the ark cover was one
span thick? What did Ibn Ezra have in mind when he added that it was "both long and
wide"?
8
Da'at Zekenim, a Tosafist commentary, Ex. 25:11.
9
According to Rashi on Sukkah 5a.
4
The solution appears to be in a similar observation made by Tashbetz,10 who remarked that
it was not logical to claim that the thickness of the ark cover was one span, "since the
thickness was only at the edges, while all of the ark cover was thin." In other words, the ark
cover was in the shape of an inverted box, hollow, with its opening facing down, and only
along the sides was it one span high (see sketch below). According to this view, it could
have weighed no more than one talent, or 42 kilograms, and it could have been one span
thick, but only along the edges, while the rest of it was thin.
10
Sefer ha-Tashbetz (Lemberg Press 1891), part 3, par. 70.
5